etimaterials-blog

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The Importance of Ring Electrodes in Biomedical Applications

When it comes to biomedical applications, Ring Electrodes play a pivotal role in ensuring the accuracy and efficiency of various medical devices. These electrodes are often integrated with Radiopaque Marker Bands to enhance their visibility during imaging procedures.

Ring electrodes are typically made from conductive materials such as Platinum-iridium alloy, which offers excellent electrical conductivity and biocompatibility. This makes them ideal for use in devices like pacemakers and neurostimulators, where reliable electrical contact is essential.

One of the key advantages of using Platinum-iridium alloy in ring electrodes is its resistance to corrosion. This ensures that the electrodes maintain their performance over time, even when exposed to bodily fluids. Additionally, the alloy's radiopacity allows for easy tracking of the device during implantation and follow-up procedures.

In some cases, ring electrodes are combined with Capillary tubes to facilitate the delivery of medications or other therapeutic agents. This combination not only enhances the functionality of the device but also improves patient outcomes by allowing for targeted treatment.

In summary, ring electrodes are a critical component in many biomedical applications. Their integration with radiopaque marker bands and use of materials like Platinum-iridium alloy ensure that they provide reliable performance and visibility, making them indispensable in modern medical technology.

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Understanding Marker Bands: The Role of Radiopaque Marker Bands in Medical Devices

Marker bands are essential components in the medical device industry, particularly in the design of catheters and guidewires. Among the various types of marker bands, Radiopaque Marker Bands stand out due to their ability to enhance visibility under X-ray imaging. These bands are typically made from materials like Tantalum or Platinum-iridium alloy, which are known for their high density and radiopacity.

Radiopaque marker bands are strategically placed on medical devices to help healthcare professionals accurately locate and position the device within the body. This is especially crucial during minimally invasive procedures, where precision is key. The use of Tantalum in these bands ensures that they are not only visible but also biocompatible, reducing the risk of adverse reactions.

In addition to their radiopacity, marker bands must be durable and resistant to corrosion. This is where materials like Platinum-iridium alloy come into play. These alloys offer excellent mechanical properties, ensuring that the marker bands maintain their integrity even under harsh conditions.

In conclusion, radiopaque marker bands are indispensable in modern medical devices. Their ability to provide clear visibility under imaging, combined with the durability of materials like Tantalum and Platinum-iridium alloy, makes them a critical component in ensuring the success of medical procedures.

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Machining processes of tungsten Ⅱ

Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. The most important properties of tungsten are high melting point and high density. Meanwhile, the hardness is high and its ductility is poor to other refractory metals. All the properties make tungsten metal hard to be machined, here we will introduce the machining process for tungsten tube & crucible, Plate, Sheet & Foil.  As tungsten’s relatively poor machability, the process & machine selection is very important. It might be crack in the process seriously, or not able to reach the tolerance. The raw material and annealing process counts a lot too. 

After sintering, the tungsten blank will be forged, to make a higher density and better mechanical properties. 

Process of tungsten plate: Thicker plate or block is forged from ingot, and ground to tight tolerance. Thinner plate or sheet are made by hot rolling process, annealing if carried between each rolling. Annealing is to make the material stress relieved, or it might be crack in the next rolling process. The selection of roller, annealing time & temper is very important, they affect the internal gain distribution, the mechanical properties of the final plates and sheets.

For the thinner sheets & foil, they are rolled from thick sheets. When down to a certain thickness, let’s say 1mm, the hot rolling process will be changed to cold rolling. It still needs to be annealed even for cold tolling.

Process of tungsten tube: Small tubes (roughly with diameter <100mm) are drilled from rods, larger tubes is made by sintering directly. Will need to make mold first if the tubes are large, you can choose a more economical way to make the tube with a critical outer diameter. Drilling from rods will waste some materials, while sintering needs a tool.

The process of tungsten crucible is similar to tungsten tube, small ones from drilling and larger ones from sintering.

Another way to make tube & crucible is welding, riveting. This is used for parts work short time and has not strictly required for leaking issues, this kind of tubes and crucibles are cheaper.

Edgetech Industries LLC provides high-precision tungsten products.

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Magnetic characteristics of permanent magnetic materials

Magnetism is the basic property of matter as well as force, heat, electricity and light. Materials with ferromagnetism are usually called magnetic materials. The biggest characteristic of magnetic materials is the hysteresis behavior, that is, the magnetization M changes with the external magnetic field. When H returns from a certain state to zero, M still maintains a certain size. Only when the magnetic field is applied in the opposite direction M drops to zero, so that the reciprocal change of M with H is a loop instead of a single curve.

Figure 1-1 shows a schematic diagram of a typical hysteresis loop.

The main parameters describing the characteristics of the hysteresis loop are:

(1) Residual magnetic induction Br, (or residual magnetic polarization Jr=AMr) (remanent magnetism for short) is the magnetic flux density when the magnetic field H=0 in the magnet;

(2) The coercive force HcB (or intrinsic coercive force HcJ) is the reverse magnetic field H necessary for the magnetic flux density B=0 (or magnetic polarization J=0);

(3) The maximum magnetic energy product (BH)max (magnetic energy product for short) is the magnetic energy product with the largest product of B and H on the demagnetization curve (the second quadrant of the hysteresis loop).

Materials with different hysteresis loops are used in different application fields. These materials are generally divided into two categories: one is soft magnetic materials with low coercivity (HcJ<100A/m), and the other is coercivity. Permanent magnet materials with large force (also called hard magnetic materials) (Hc>1000A/m).

The characteristic of the permanent magnet is that after being magnetized by the external magnetic field, the magnetic field can be kept stable for a long time after the external field is removed. The most comprehensive criterion for the performance of permanent magnetic materials is the shape of the demagnetization curve under various external conditions (external magnetic field, temperature, time, radiation, vibration, etc.), but for simplicity, usually only the above mentioned Three parameters and its stability are measured: the size of the magnetic energy product (BH)max, which characterizes the ability of permanent magnets to provide magnetostatic energy, that is, in the case of meeting the same magnetic field value and spatial range, (BBD) large materials are used Less material; the greater the residual magnetization Br, the greater the magnetic field strength that the magnet may provide to the space; and the material with a large HcJ has strong anti-interference ability. Therefore, the higher the above three parameters, the better the magnetic properties of the permanent magnet. The temperature stability of permanent magnetic materials mainly refers to the temperature coefficient and irreversible loss of the material. The temperature coefficient (or reversible temperature coefficient) refers to the percentage of reversible change in residual magnetism or coercive force when the temperature changes. The irreversible loss refers to the rate of change of the open-circuit magnetic flux starting from room temperature and returning to room temperature after heating or cooling. For permanent magnetic materials, the smaller the absolute value of the temperature coefficient and the irreversible loss, the better.

We mainly provide rare earth permanent magnets, including neodymium iron boron magnets and samarium cobalt permanent magnets.

永磁材料的磁性特征

磁性与力,热,电,光一样是物质的基本属性. 具有铁磁性的材料通常称为磁性材料。磁性材料的最大特征就是具有磁滞行为即磁化强度M随外磁场互变化的滞后行为，当H从某个状态回到零时，M还保持一定的大小，只有在反方向施加磁场才会将M降到零，从而M随H的往复变化呈回线而非单的曲线。图1-1给出了典型磁滞回线的示意图。描述磁滞回线特征的主要参数是:

剩余磁感应强度Br，(或剩余磁极化强度Jr=AMr)(简称剩磁)，是磁体内部磁场H=0时的磁通密度;

矫顽力HcB(或内禀矫顽力HcJ)，是使磁通密度B=0 (或磁极化强度J=0)所必须的反向磁场H;

最大磁能积(BH)max(简称磁能积)，是退磁曲线(磁滞回线第二象限部分)上B和H乘积最大的磁能积。

具有不同磁滞回线的材料用于不同的应用领域，这些材料通常划分为两大类:一类是矫顽力较小的软磁材料(HcJ＜100A/m)，另一类是矫顽力较大的永磁材料(也称硬磁材料)(Hc＞1000A/m)。

永磁体的特征是在受外磁场磁化后，撤去外场仍能长时间稳定地保持磁性。永磁材料性能的好坏，最全面的判据是在各种外界条件(外磁场、温度、时间、辐射、振动等)下的退磁曲线的形状，但为了简便起见，通常只用上面提到的三个参数及其稳定性来衡量:磁能积(BH)max的大小，表征永磁体提供静磁能的能力，即在满足同样的磁场值和空间范围的情况下，(BBD)大的材料用料少;剩磁Br越大，磁体可能向空间提供的磁场强度越大;而HcJ大的材料，抗干扰能力强。所以，上述三个参数越高，永磁体磁性能越好。永磁材料的温度稳定性主要是指材料的温度系数和不可逆损失。温度系数(或称可逆温度系数)是指温度改变时，剩磁或矫顽力可逆改变的百分比。不可逆损失是指由室温开始，经过加热或冷却再回到室温时开路磁通的变化率。对永磁材料来说，温度系数的绝对值和不可逆损失越小越好。

我们主要提供稀土永磁磁铁，包括钕铁硼磁铁和钐钴永磁铁。

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The performance influencing factors of pyrolytic boron nitride

The production efficiency of boron nitride produced by chemical vapor deposition is high, but this method is easy to introduce pores and impurities into the sintered body and anisotropy caused by hot pressing. This makes its application very limited, especially in high temperature and oxidizing environments. Pyrolytic boron nitride materials have excellent physical and chemical properties. Chemical vapor deposition (CVD) is an ideal choice for the preparation of high-purity and dense boron oxide materials. The structure, morphology and properties of the prepared pyrolytic boron nitride (PBN) may depend to a large extent on the process conditions.

Most boron nitride prepared by chemical vapor deposition (CVD) is thin film, powder, etc., while bulk boron nitride is limited to highly anisotropic pyrolytic boron nitride, which cannot fully utilize the characteristics of structural diversity. The synthesis of boron nitride limits its application in a wider field. Therefore, there are relatively few studies on isotropic pyrolytic boron nitride with excellent mechanical properties.

In view of the wide application of pyrolytic boron nitride, it is necessary to further study the preparation process of pyrolytic boron nitride material, especially the deposition mechanism.

It provides a solid foundation for the controllable preparation of pyrolytic boron nitride. High-purity, high-density pyrolytic boron nitride (PBN) materials can be prepared by chemical vapor deposition (CVD) and appropriate control of process parameters. The pyrolytic boron nitride material prepared by the method has good processing properties and can meet application requirements.

Many technical parameters affect the preparation of pyrolytic boron nitride (PBN), including boron nitrogen source, temperature, pressure and reactor structure. The reaction gas of boron nitride is mainly divided into two types: boron nitrogen carrier gas/diluent gas, and compound carrier gas/diluent gas containing boron and nitrogen. The deposition temperature of boron nitride can be varied in a wide range (250°C-2300°C). The higher the total temperature, the better the crystallinity of the deposited boron nitride.

The deposition pressure of boron nitride varies from 1 to 760 Torr. The deposited substrate may be a porous substrate such as excess metal, structural ceramics, electronic ceramics, glass, graphite and ceramic particles.

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Basic Information of Pyrolytic boron nitride (PBN ceramic)

Pyrolytic boron nitride is an anisotropic high-temperature ceramic with high electrical resistance and good thermal conductivity. It is suitable for applications requiring high strength, low thermal expansion coefficient and good thermal shock resistance. Pyrolytic boron nitride also has thermal shock resistance and is a superior sealant that protects graphite from corrosive environments, such as most molten metals, acids, and hot ammonia environments. It has been verified that pyrolytic boron nitride is also a very effective insulating material. Pyrolytic boron nitride is non-toxic and harmless under normal conditions, has no porosity, and has high purity, so it is easy to store and easy to process into crucibles, evaporation boats, plates, pipes, bottles and other utensils. 

Pyrolytic Boron Nitride (PBN) belongs to the hexagonal crystal system. It is an advanced ceramic material with a purity of 99.999%, acid and alkali resistance, oxidation resistance, good thermal conductivity, compactness, and processing. It is formed by chemical vapor deposition (CVD) of ammonia and boron halides under high temperature and high vacuum conditions. It is different from ordinary hot-pressed boron nitride (BN). It does not need to go through the traditional hot-pressed sintering process. Add any sintering agent, so the obtained product has the following remarkable characteristics:

-Non-toxic and odorless;

-High purity, up to 99.999%;

-It does not react with acids, alkalis, salts and organic reagents at room temperature, and slightly corrodes in molten salt and lye, but it can resist the corrosion of various acids at high temperatures;

-Does not react with most molten metals, semiconductors and their compounds;

-Below 1000℃, good oxidation resistance;

-Good thermal shock resistance, no cracks are found when thrown into water at 2000℃;

-High operating temperature, no sublimation point, directly decomposed into B and N above 3000℃;

-High resistance, good electrical insulation performance;

-Smooth surface, no pores, and non-wetting with most semiconductor melts.

Applications of PBN

-OLED evaporation unit

-Semiconductor single crystal growth (VGF, LEC) crucible

-Molecular beam epitaxy (MBE) evaporation crucible

-MOCVD heater

-Polycrystalline synthesis boat

-PBN infrared window

-Satellite communication microwave tube

-PBN coated carrier plate

-Insulation board for high temperature and high vacuum equipment

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An Overview of Advanced Ceramics

Advanced ceramics can be divided into structural ceramics, tool ceramics, and functional ceramics according to their different uses.

Structural Ceramics

The main materials of structural ceramics are alumina (Al2O3), silicon nitride (Si3N4), silicon carbide (SiC), and hexagon boron nitride ceramics (BN).

Alumina (Al2O3)

The main composition is Al2O3, and the general content is more than 45%. Alumina ceramics have various excellent properties such as high-temperature resistance, corrosion resistance and high strength, which is 2~3 ordinary ceramics. However, alumina ceramics have the disadvantage of being brittle and unable to accept sudden changes in ambient temperature. Alumina ceramics are widely used as the crucible, engine spark plug, high-temperature refractory, thermocouple sleeve, sealing ring and so on.

Silicon nitride (Si3N4) ceramics

Si3N4 is the main component of silicon nitride ceramics, which is a kind of high-temperature ceramics with high strength, high hardness, abrasion resistance, corrosion resistance, and self-lubrication. The linear expansion coefficient of silicon nitride is the smallest among all kinds of ceramics, and it has excellent electrical insulation and radiation resistance. It has excellent corrosion resistance, and it can withstand the corrosion of various acids except the hydrofluoric acid, as well as alkali, corrosion of various metals. Silicon nitride ceramics can be used as high-temperature bearings, sealing rings used in corrosive media, thermocouple sleeves, and metal cutting tools.

Silicon carbide ceramics (SiC)

Silicon carbide ceramics are mainly composed of SiC, which is a kind of high-temperature ceramic with high strength and high hardness. When used in the high temperature of 1200 ℃ ~ 1400 ℃, silicon carbide ceramics can still maintain a high bending strength. In addition, silicon carbide ceramics also have good thermal conductivity, oxidation resistance, electrical conductivity, and high impact toughness. It is a good high-temperature structural material and can be used for rocket tail nozzle, thermocouple sleeve, furnace tube, and other high-temperature components.

Hexagonal boron nitride (h-BN)

The main composition of hexagonal boron nitride ceramics is BN, and the crystal structure is hexagonal crystal system. The structure and performance of hexagonal boron nitride ceramics are similar to graphite, so it is known as “White Graphite “. Hexagonal boron nitride ceramics are of low hardness and can be machined with self-lubricating properties, and they can also be made into self-lubricating high-temperature bearings and glass-forming molds.

Tool Ceramics

The main materials of tool ceramics are cemented carbide, natural diamond (diamond), cubic boron nitride (CBN), etc.

Cemented carbide

Carbides are mainly composed of carbides and binders. Carbides mainly include WC, TiC, TaC, NBC, VC, etc., and binders are mainly cobalt (Co). Compared with the tool steel, cemented carbide has a high hardness (87 ~ 91 HRA), good red hardness (1000 ℃) and excellent wear resistance. When used as a cutter, its cutting speed is 4~7 times higher than that of HSS, and its service life is 5~8 times higher. However, its disadvantages are high hardness, brittle, and difficult to be machined, so it is often made into a blade and welded on the tool rod for use. Carbide is mainly used for machining tools; Various dies, including drawing die, drawing die, cold heading die; Mining tools, geology, and petroleum use a variety of drill bits, etc.

Natural diamond (diamond)

Natural diamond (diamond) is a precious ornament, while synthetic diamond is widely used in the industry. Diamond is the hardest material in nature and has a very high elastic modulus, and the thermal conductivity of diamond is the highest among known materials. Besides, diamond has good insulation, which can be used as the drill bit, cutter, grinding tool, drawing die, dressing tool. However, the thermal stability of the diamond tool is poor, and the affinity with iron group elements is large, so it cannot be used for processing iron, nickel-based alloy, but mainly for processing non-iron metal and non-metal, widely used in ceramics, glass, stone, concrete, gem, agate and other processing.

Tool Ceramics

•           Cubic boron nitride (CBN)

Cubic boron nitride (CBN) has a cubic crystal structure, and its hardness is second only to diamond. The thermal and chemical stability of cubic boron nitride is better than that of diamond, and it can be used for cutting hardened steel, wear-resisting cast iron, thermal spraying material, nickel, and other difficult materials.

•           Other tool ceramics

Other tool ceramics are alumina, zirconia, silicon nitride, and other ceramics, but they are not as good as the above three tool ceramics from the comprehensive performance and engineering applications.

Functional Ceramics

Functional ceramics usually have special physical properties and cover many fields, and the characteristics and applications of common functional ceramics are as follows.

•           Dielectric ceramics

Performance: Insulation, thermoelectric, piezoelectric, strong dielectric

Material composition: Al2O3, Mg2SiO4, BaTiO3, PbTiO3, LiNbO3

Application: Integrated circuit substrates, thermistors, oscillators, capacitors

•           Optical ceramic

Performance: Fluorescence, luminescence, infrared transmittance, high transparency, the electrochromic effect

Material composition: Al2O3CrNd glass, CaAs, CdTe, SiO2, WO3

Application: Laser, infrared window, optical fiber, display

Functional Ceramics

•           Magnetic Ceramics

Performance: Soft magnetism and hard magnetism

Material composition: ZnFe2O, SrO, y-Fe2O3

Application: Magnetic tape, all kinds of the high-frequency magnetic core, electro-acoustic devices, instruments and control devices of the magnetic core

•           Semiconductive ceramics

Performance: Photoelectric effect, resistance temperature change effect, thermionic emission effect

Material composition: CdS, Ca2Sx, VO2, NiO, LaB6, BaO

Application: Solar cells, temperature sensors, the hot cathode

Development of advanced ceramics

Advanced ceramic is a significant piece of new material, broadly utilized in correspondence, hardware, flying, aviation, military, and other fields, and has significant applications in data and correspondence innovation.

Most utilitarian pottery are broadly utilized in the gadgets business, which is frequently alluded to as electronic artistic materials. For instance, clay protection materials utilized in chip producing, fired substrate materials, earthenware bundling materials, and capacitor ceramics, piezoelectric ceramics, ferrite attractive materials utilized in electronic gadgets fabricating.

As of now, progressed pottery has framed a high-tech industry. Overall deals of high-tech earthenware production surpass the US $30 billion and are developing at a yearly pace of over l0%, with the United States and Japan driving the field. Progressed earthenware materials assume an undeniably significant part in industry, conventional industry change, and public guard and military industry because of their great high-temperature mechanical properties and their special composite impacts of light, sound, power, attraction, warmth, or capacity.

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Overview of Nitinol Material

Titanium nickel alloy, also known as Nitinol, is a binary alloy composed of nickel and titanium. The atomic percentages of these two elements are approximately equal.

Austenitic phase and martensite phase

Due to changes in temperature and mechanical pressure, Nitinol has two different crystal structure phases, namely an austenite phase and a martensite phase. In Nitinol, austenite is called the mother phase, which is the crystalline phase of the alloy at high temperatures. When the temperature decreases, austenite will gradually transform into martensite (child phase).

Two characteristics of Nitinol

-Shape memory

When the mother phase of a certain shape cools from above the Af temperature to below the Mf temperature and completely forms martensite, shape memory occurs, thereby deforming the martensite below the Mf temperature. After heating below the Af temperature, the material will automatically recover its parent phase shape by reverse phase transition. In fact, the shape memory effect is a thermally induced phase transformation process of nitinol. It refers to the ability of Nitinol to deform at a certain temperature and then restore its original, undeformed shape when the temperature is higher than its "transition temperature".

-Super elastic

The so-called superelasticity refers to the phenomenon that the strain generated by the sample under the action of external force is much greater than the elastic limit strain, and the strain will automatically recover during the unloading process. In the parent phase, due to the effect of external stress, the strain triggers the martensite transformation, so the alloy exhibits different mechanical properties from ordinary materials. Its elastic limit is much larger than ordinary materials. And it no longer follows Hooke& #39;s law. Compared with the shape memory effect, superelasticity does not involve heat.

Application of Nitinol

1. Glasses frame

2. Orthodontics

3. Medical equipment

4. Other applications

A well-known computer manufacturer used Nitinol equipment to eject PCMCIA (International Personal Computer Memory Card Association) cards. In addition, Nitinol is also used to connect the end of the aircraft hydraulic tubing. In less severe applications, nitinol can bend the magic shop spoon when it is placed in hot water.

https://www.edge-techind.com/Products/Non-ferrous-Metals/Titanium-Ti/Nitinol/Nitinol-Tube-780-1.html

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Superelasticity and Shape Memory of Nitinol

Nitinol (Nitinol) alloys have many material and device characteristics, for example, kinking resistance, stress constancy, dynamic interference, deflection stiffness, magnetic resonance imaging (MR1) compatibility, radiopacity and biocompatibility. The most famous characteristics of Nitinol are its superelasticity and thermal shape memory. Although the term "shape memory" describes the phenomenon of restoring a predetermined shape by hearing and deforming the shape "plastically", the term "superelasticity" refers to the great elasticity of these alloys, which can be 10 times greater than the best stainless steel. Steel used in medicine today. Although both effects are spectacular, they are not the only important properties of the material.

Nitinol has two characteristics: shape memory effect (SME) and superelasticity (SE).

Shape memory Shape memory happens when mother phase of a certain shape is cooled from above the Af temperature to below the Mf temperature and completely forms the martensite, deforming the martensite below Mf temperature. After being heated to below Af temperature, with reverse phase transformation, the material will automatically restore its shape in mother phase. In fact, the shape memory effect is a thermally induced phase transition process of nitinol. It refers to ability of nitinol to deform at a certain temperature and then restore the original, non-deformed shape when the temperature is higher than its "transition temperature".

Superelasticity The so-called superelasticity refers to the phenomenon in which the sample produces a strain that is far greater than the elastic limit strain under the effect of external forces and the strain can automatically restore during unloading. In mother phase, due to the effect of external stress, the strain triggers martensitic phase transition so that the alloy exhibits mechanical behaviors that are different from those of ordinary materials. Its elastic limit is much larger than that of ordinary materials. And it no longer follows Hooke’s Law. Compared with shape memory effect, superelasticity does not involve heat.

The unique characteristics of these nickel-titanium alloys combined with strength, fatigue resistance, biocompatibility, and MRI compatibility provide an interesting solution for the design of advanced medical devices. Conventional metal materials used for stents, filters, and other interventional devices exhibit elastic deformation behaviors that are very different from those of human body structures. Nitinol alloys have similar behaviors. Nitinol is an aromatic or near-equiatomic intermetallic compound of titanium and nickel.

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Maximizing Efficiency with Silicon Nitride in High-Temperature Applications

Welcome to our latest blog post, where we delve into the world of high-temperature applications and how to maximize efficiency with silicon nitride. Whether you are an engineer or a business owner in the aerospace, automotive, or energy industries, understanding the importance of choosing the right materials for high-temperature environments is crucial. Enter silicon nitride – a versatile ceramic material that has gained popularity for its exceptional thermal and mechanical properties. In this post, we will explore why silicon nitride is becoming increasingly prominent in high-temperature applications and how it can help businesses improve their performance, reduce costs, and stay ahead of their competition. So buckle up as we take a deep dive into this powerful material that is revolutionizing industries all over the world!

Unveiling the Secrets of Silicon Nitride's Thermal Stability

Silicon nitride ceramics have long been renowned for their exceptional thermal stability. By carefully uncovering the secrets of this unique material, scientists have gained valuable insight into how silicon nitride ceramics maintain their impressive durability even under extreme conditions. From its unique crystal structure to its ability to resist oxidation and corrosion, silicon nitride ceramics have proven to be a standout material in the world of engineering. By continuing to explore the mysteries of silicon nitride ceramics, researchers are paving the way for even greater advancements in fields such as aerospace, energy, and electronics.

Pioneering Uses of Silicon Nitride in Extreme Environments

Silicon Nitride Ceramics has opened up new frontiers in materials science, creating a revolutionary class of high-performance materials with unparalleled strength, durability, and corrosion resistance. Their unique properties make them ideal for use in extreme environments, where conventional materials like steel, aluminum, and other metals fall short. Pioneering uses for Silicon Nitride Ceramics include everything from bearings and cutting tools to aerospace components, where they offer superior performance and longevity compared to traditional materials. With their potential to unlock new possibilities in a wide range of industries, Silicon Nitride Ceramics are poised to transform the world of materials science.

Comparing Silicon Nitride with Other High-Temperature Materials

Silicon Nitride ceramics are known to have exceptional properties that make them one of the most reliable and high-performing high-temperature materials in the market. Compared to other materials, this ceramic exhibits a unique blend of strength, toughness, and resistance to wear and thermal shock. Silicon Nitride ceramics stand out as a versatile and cost-effective solution for many applications in diverse industries such as power generation, aerospace, and automotive. Other high-temperature materials such as ceramics, metals, and alloys may have certain merits, but Silicon Nitride ceramics continue to dominate in terms of high-temperature performance, offering a reliable and efficient solution for challenging environments.

In conclusion, it is evident that silicon nitride ceramics have proven to be an invaluable material in multiple industries due to its exceptional thermal stability. From its pioneering uses in extreme environments such as aerospace and automotive engines, to its continued success in various high-temperature applications, it is clear that silicon nitride ceramics are here to stay. As we continue to explore the secrets of this remarkable material, the possibilities for its use seem endless. So why not join us on this exciting journey and see where silicon nitride can take us next? Whether you are an engineer looking for a solution to your extreme environmental problems or simply have a curiosity about advanced materials, the potential for silicon nitride is undeniable. Let's push the boundaries together and discover even more revolutionary uses for this versatile ceramic. Don't wait, start exploring the world of silicon nitride today!

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Applications of Strong Neodymium Magnets Across Industries

Are you looking for a way to make your industrial processes more efficient and reliable? Strong neodymium magnets may be the answer. By leveraging the power of these powerful, permanent magnets, many industries have been able to overcome unique challenges with ease. From providing a solution for remote robotic equipment control in hazardous environments to powering cutting-edge hospital imaging machines, neodymium magnets continue to push technological boundaries every day. In this blog post, we'll take an in-depth look at how various industries are using strong neodymium magnets as remarkably versatile tools as well as discuss practical applications for your own operations. Join us and discover why so many experts consider these rare earth superalloys essential components in our modern world!

Magnetic Innovations: Neodymium's Role in Cutting-Edge Technologies

Magnetic Innovations have brought about a revolution in the world of technology. Neodymium, a rare earth element, plays a significant role in the achievement of these novel advancements. It is widely used in applications like electric motors, hard disk drives and headphones, as it possesses extremely strong magnetic properties. The development of tiny, yet powerful neodymium magnets has enabled the creation of compact and efficient devices. The spectrum of magnetic innovations is constantly expanding, with researchers exploring the use of neodymium in energy storage, medical imaging and even levitating trains. The fascinating possibilities offered by this magnetic wonder, truly showcase the potential of technology in shaping the future.

Engineering Excellence: Strong Neodymium Magnets in Aerospace

Neodymium magnets are a wonder of engineering excellence, widely used in aerospace. They are the strongest type of permanent magnet commercially available and are critical in various aerospace applications, including sensors, generators, actuators, and more. Their remarkable strength allows them to perform a wide range of functions in an extremely efficient and reliable manner, making them essential components of advanced aerospace technology. Neodymium magnets are designed to withstand extreme temperatures, high pressure, and other harsh environmental conditions that are common in space missions. With their incredible magnetic strength and durability, neodymium magnets are a true testament to the possibilities of engineering excellence in aerospace.

Driving Efficiency: Neodymium Magnets' Impact on Automotive Systems

Neodymium magnets have made a significant impact on the automotive industry by improving overall efficiency. These powerful magnets are used in various automotive systems, such as electric powertrains and hybrid vehicles, making them more energy-efficient and eco-friendly. Neodymium magnets have a unique ability to produce a powerful magnetic field, making them ideal for use in motors and generators. This makes them a crucial component in electric vehicles as they help convert electrical energy into kinetic energy which helps power the vehicle. By integrating neodymium magnets into automotive systems, it is possible to achieve greater fuel efficiency and reduce the carbon footprint of cars and other vehicles. With technology advancements, the use of neodymium magnets is predicted to grow further in the coming years, and the automotive industry is poised to benefit from it significantly.

The most effective and useful solutions of today’s world depend heavily on the use of powerful components. This is where neodymium magnets come into play as they can make a tremendous impact in modern industries such as aerospace and automotive systems. Not only do these components offer great power, but their strength and flexibility make them easily adaptable to many uses. With its amazing features and versatility, neodymium has become an incredibly valuable asset in groundbreaking applications and will remain so for years to come. If you're looking to explore the possibilities for what neodymium can offer your business, contact us today and learn more about how this incredible magnet can help you achieve success in innovative designs!

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Process of high-density tungsten alloy

High-density tungsten alloy, also known as tungsten-based heavy alloy, is a type of alloy made of tungsten as the matrix element (85% ~ 99% mass fraction) with the addition of Ni, Cu, Fe and other alloy elements by liquid phase sintering. The density is up to 16.5 ~ 19.0g / cc. The most commonly used are tungsten nickel copper and tungsten nickel iron alloy with tungsten content of 90% -97%. Tungsten nickel copper alloy is a non-magnetic alloy, while tungsten nickel iron is a magnetic alloy. W-Ni-Fe series alloys are widely used because they have better mechanical properties than W-Ni-Cu series alloys.

High-density tungsten alloy is traditionally prepared by powder metallurgy, and its sintering process is as follows:

Powder ---- Mixing --- Pressing --- Sintering --- Heat treatment --- Plastic deformation (Forging, rolling) --- Annealing-Product

Some products can also be directly obtained by sintering.

Sintering

The sintering of high-density tungsten alloys mostly adopts liquid phase sintering process: normally, the sintering temperature is higher than the liquid phase temperature by 20 to 60 ℃. The sintering temperature of W-Ni-Fe alloy is 1500～1525 ℃, the density can be close to the theoretical density, the holding time is generally 60～90min. If it exceeds 120min, the performance will drop. The use of higher sintering temperature and shorter holding time is beneficial to improve the tensile strength and elongation of the alloy. The choice of cooling rate is related to the m(Ni)/m(Fe) ratio of the alloy. When this ratio is not in the range of forming brittle compounds, such as the m(Ni)/m(Fe) ratio of 2 to 4, any cooling rate will not generate intermetallic compounds. To avoid brittleness and reduce porosity, it is beneficial to use an appropriate cooling rate.

Heat treatment

Post-sintering heat treatment includes: quenching, rapid cooling, atmospheric dehydrogenation treatment and surface hardening treatment, the purpose is to reduce the segregation of P, S and other impurities at the interface, reduce hydrogen embrittlement, improve alloy performance or meet other alloy performance requirements. Quenching and rapid cooling treatment can obtain a fine and uniform grain structure, better play the role of solid solution strengthening, and increase the strength of the alloy by 1/3 to 1/2.

Heat treatment can improve the mechanical properties of the alloy obviously. Studies have shown that if the 95W alloy is placed in an intermediate frequency induction furnace with a vacuum of 0.133-0.0133Pa for vacuum heat treatment (temperature 850 ℃ -900 ℃, holding 40min), the strength and impact toughness of the alloy will be significantly improved.

Plastic deformation processing

In order to improve the mechanical properties of the alloy, various plastic deformation processes are carried out on the sintered high-density tungsten alloy. At present, large-diameter tungsten alloy core materials with a length/diameter ratio greater than 8 are generally prepared by deformation strengthening technology. Deformation strengthening techniques include forging, hydrostatic extrusion, hot extrusion, hot rolling, or hot extrusion and forging composite deformation processes.

After dehydrogenation of high-density tungsten alloy by vacuum heat treatment, hydrogen embrittlement is weakened, phase boundary strength is improved, and the strength and plasticity of the alloy are greatly improved, which provides favorable conditions for high plasticization of the plastic deformation of the alloy. In the deformation strengthening process, the amount of deformation has a very important effect on the performance of the tungsten alloy. As the amount of deformation increases, the strength and hardness of the alloy increase, while the ductility decreases. In order to greatly improve the mechanical properties of the alloy, in recent years, a large deformation strengthening technology for high-density tungsten alloys has been developed. The strength of large deformation is increased by more than 300MPa than that of ordinary forging. For high-density tungsten alloy armor-piercing core materials with an aspect ratio of about 16 and a tensile strength of about 1200 MPa, one-time forging deformation strengthening can meet the requirements. For the new high-density tungsten alloy armor-piercing projectile in research and development, it must undergo multiple cycles of forging and deformation to meet the requirements.

Machining

After plastic deformation, the appropriate machining method can be selected according to the drawings, such as: turning, milling, cutting, drilling, polishing, etc.

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Overview of rare earth metals and intermediate alloys

The vast majority of single rare earth metals and their intermediate alloys are used to produce new rare earth metal materials such as neodymium iron boron, samarium cobalt permanent magnet and super magnetostriction and non-ferrous metal alloys such as AI-RE, Mg-RE, Cu-RE, Zn- RE, W-RE, Mo-RE, etc. In addition, there are a few rare earth metal applications that use some special properties to prepare functional materials.

Neodymium metal, praseodymium and praseodymium neodymium alloy

Neodymium has the hard-magnetic properties caused by the good 4f electron spin arrangement, and has become the largest user of neodymium iron boron permanent magnet materials. In recent years, the global neodymium iron boron materials have developed rapidly, and the large application of neodymium metal in neodymium iron boron permanent magnet materials has driven the rapid development of the rare earth industry. In addition, neodymium metal as an alloy additive has good purification, modification and alloying effects on many non-ferrous metal alloys. Adding 1.5%-2.5% neodymium to magnesium or aluminum alloy can improve the high temperature performance, air tightness and corrosion resistance of the alloy.

Praseodymium is a synergistic element that can improve magnetic properties. Adding an appropriate amount of praseodymium to samarium drill permanent magnets and neodymium iron boron permanent magnets can effectively improve and improve the performance of permanent magnetic materials. Adding part of Pr to SmCo5 to replace Sm can improve the magnetic energy product of water magnetic materials. Adding 5% to 8% Pr to NdFeB, up to 10% can replace 13 neodymium alloy, which can improve the magnet's oxidation resistance, coercive force and Mechanical properties. The neodymium alloy has become an independent product, which can be used not only in water magnetic materials, but also as a non-ferrous metal alloy modification additive.

Dysprosium and terbium

Metal dysprosium and dysprosium iron alloys and metal terbium and terbium iron alloys are used as modifying additives for high-performance NdFeB permanent magnet materials. Adding 2% to 5% of metal dysprosium and lower amounts of metal terbium in the NdFeB magnet It can significantly improve the coercivity and service temperature of NdFeB permanent magnet materials. Dysprosium and terbium are essential elements for preparing rare earth giant magnetostrictive materials (Tb0.3 Dy0.7Fe1.95 alloy, called Terfenol-D). The magneto-optical properties of dysprosium and terbium are used to prepare amorphous thin-film RE-TM high-performance magneto-optical discs with transition metals. Dysprosium metal is alloyed with some nonferrous metals and precious metals, such as a film sputtering target with dysprosium added to a silver alloy, which can be used as a wiring film or a reflective film for flat panel display devices.

Samarium Metal

Samarium metal has excellent hard magnetic properties and is used as the main raw material for the preparation of SmCo5, Sm2Co17, Sm2Fe17Nx permanent magnet materials. The samarium thermal neutron trap has a large cross section, reaching 650 MPa, and metal samarium is made into rods for controlling the amount of thermal neutrons in the nuclear reactor. Samarium as a non-ferrous metal micro-alloying additive such as Cu added Sm to generate SmCu5 intermetallic compounds play a role of micro-alloying, improve the mechanical properties and workability of copper alloys.

Metal lanthanum

The metal lanthanum is active and used as a metal reducing agent. The thermal reduction process is used to reduce other rare earth metals. Lanthanum is also used as a purifying agent and modifier for non-ferrous alloys. It is usually used in the form of a lanthanum intermediate alloy. Lanthanum metal is used to make LaN5i alloy. It is an excellent hydrogen storage material. It can store about 160L of hydrogen per kilogram. It can absorb and release hydrogen. It can be used as a hydrogen purifier to purify hydrogen with a purity of 99.999%. To 99.9999%.

Metal yttrium, cerium, scandium and gadolinium

Metal yttrium and cerium are excellent scavengers and modification additives for nonferrous metals such as magnesium, aluminum, and titanium. Yttrium-magnesium alloy has good high-temperature mechanical properties and excellent high-temperature oxidation resistance, and is used as a lightweight structural material in aviation and aerospace. The addition of 0.5%-4% yttrium metal to the iron-chromium aluminum alloy can improve the oxidation resistance of the alloy, increase the resistivity and high-temperature strength; iron-chromium-aluminum stainless steel containing metal cerium has been widely used as a metal platinum carrier for motorcycle exhaust purification catalysts. Scandium metal is a high-quality modified additive element of aluminum, magnesium and titanium. Adding 0.2%-0.4% Sc to aluminum can significantly improve the high temperature strength, alloy structural stability, welding performance and corrosion resistance of aluminum alloys. The world has developed a series of aluminum scandium and magnesium scandium alloys with excellent performance, which are ideal aerospace materials. Scandium metal is also used in neutron generators, which can produce high-energy neutrons and is a neutron source for activation analysis and geological prospecting. Gadolinium metal is a more suitable magnetic refrigeration material, and gadolinium and gadolinium intermetallic compounds are used as working materials for magnetic refrigeration. In addition, metal gadolinium and gadolinium-iron alloys have been used as neodymium-iron-boron hydromagnetic materials as additives to replace some of the metal dysprosium, which can not only improve the performance of the magnet but also make up for the lack of supply of metal dysprosium.

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Nitinol Applications

Although many nitinol applications are not well-known to the public, some applications are quite routine and familiar.

The spectacle frame made of Nitinol severely deformed and then returned to normal. Similarly, a few years ago, when mobile phone antennas were made of Nitinol, they could bend without breaking or permanently bending.

Another superelastic application of Nitinol is for orthodontic archwires. The orthodontist uses fixed nitinol wire to fix the teeth. Since the wire is super-elastic, it will try to restore its straight state and continue to exert force on the teeth. This can reduce frequent visits to orthodontists to tighten braces.

Many little-known applications use Nitinol's shape memory function. A well-known computer manufacturer used Nitinol equipment to eject PCMCIA cards. In addition, Nitinol is also used to connect the end of the aircraft hydraulic tubing. Nitinol can make the magic shop spoon bend in hot water also because of its shape memory function

Nitinol's superelasticity and biocompatibility make it an ideal choice for manufacturing a variety of medical devices implanted in the human body. For example, a stent is a device that supports blood vessels and keeps them open. Nitinol's superelasticity can compress medical devices, such as stents or heart valves, into a shape that fits inside the catheter. Place the catheter in the correct position in the body, release the device, and then restore its original shape. Its superelasticity makes Nitinol the only material suitable for stents in the neck and carotid arteries or legs. In these vulnerable locations, a blow to the stent area will cause it to deform, but the Nitinol stent will return to its intended shape. Brackets made of other materials may be crushed or permanently bent by this impact.

Surgical instruments and components made of Nitinol can meet many needs, especially in minimally invasive or arthroscopic surgery. These can utilize the superelasticity and fatigue resistance of Nitinol. Tools with elbows can be straightened and inserted through casings and rigid tubes. When it comes out of the casing, the tool will return to its original shape. The surgeon performs this procedure, then retracts the tool into the cannula and straightens it again to facilitate disassembly.

With the development of technology, Nitinol will also be applied in a wider and more delicate field, we will wait and see.

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Interaction between rare earth metals and other elements

Rare earth metals have typical metal properties. They have strong chemical activity and can form a variety of compounds, including hydrides, chlorides, silicides, carbides, organic / inorganic salts and complexes. This is the basis for the rare earth metal in the metallurgical industry as a purification, impurity removal and refinement modifier.

Rare earth metals are unstable in air, and their stability increases with increasing atomic number; in other words, the rare earth metals with larger atomic radius have weaker oxidation resistance; light rare earth metals can be easier oxidized than heavy rare earth metals, and lanthanum is the most active. Lutetium and Scandium are the most resistant to air oxidation.

Rare earth metals are widely used as reducing agents, which can reduce oxides of iron, cobalt, nickel, chromium, vanadium, niobium, tantalum, zirconium, titanium, silicon and other elements into metals. Due to the difference in the reducing ability of rare earth metals, and the vapor pressure of the lanthanum is much smaller than that of Samarium, Europium, Ytterbium and Thulium, Lanthanum (cerium) can be used to reduce europium, europium, europium, europium metal from its oxides. However, the activity of rare earth metals is lower than that of alkali metals and alkaline earth metals, so lithium and calcium are commonly used as reducing agents to reduce rare earth metals from their halides.

Interactions between rare earth metals occur. If the two rare earth metals have the same crystal structure at the corresponding temperature, they can form a continuous solid solution; if the two rare earth metals have different crystal structures, they can only form a finite solid solution; Only two rare earth metals belonging to different subgroups (cerium and yttrium) can form intermetallic compounds.

The behavior of Yttrium and scandium in alloys is similar to that of heavy rare earth metals; the behavior of Ytterbium in magnesium alloys is similar to that of light rare earths. The melting point and elastic modulus of Europium and Ytterbium are similar to those of light rare earth lanthanum and cerium.

Rare earth metals and transition metals (iron, manganese, nickel, gold, silver, copper, zinc) and magnesium, aluminum, gallium, indium, thallium can form many alloys. Moreover, many intermetallic compounds are formed in their binary and multicomponent alloys.

Some of these compounds have high melting points, high hardness, high thermal stability, and are dispersed in the non-ferrous alloy matrix or grain boundaries. They play an important role in resisting high temperature, creep resistance, and improving the strength of the alloy. Many of these rare earth intermetallic compounds have been widely used in high and new technology with special functions. It is expected that more new intermetallic compounds will be developed in succession.

Only tantalum / niobium and tungsten / molybdenum and their alloys have little interaction with rare earth metals. Tantalum and molybdenum have almost no interaction with rare earth metals and their halides. Under vacuum or inert gas, tantalum can be used at 1700 °C, molybdenum can be used at 1400 °C, and it is used as the electrode for molten salt electrolysis and the carrying crucible for rare earth metals and rare earth alloys.

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Heat treatment of niobium and niobium alloys

The finished products of niobium and niobium alloy materials and their processing and preparation processes need to be annealed and heat treated. The heat treatment methods include homogenization heat treatment, stress relief heat treatment, recrystallization heat treatment and mechanical heat treatment.

-Homogenization heat treatment. The homogenization heat treatment is to eliminate defects such as metastable phases and component segregation in the ingot by atomic diffusion, and to make the structure uniform and stable.

The homogenization temperature of the niobium ingot is 1800~2000 ℃, the vacuum degree is 10-2~10-3Pa, and the holding time is 5-10h.

-Stress-relief heat treatment. The purpose of stress-relief annealing is to eliminate or reduce the internal stress of the material and improve the mechanical and technological performance of the material. Therefore, at a given temperature, the stress and strain energy can be eliminated quickly.

-Recrystallization heat treatment. The recrystallization heat treatment can eliminate the processed structure and restore the properties of the material to the state before deformation. Through the interaction of deformation and recrystallization annealing, component segregation can be eliminated, the grains can be broken, the structure can be uniform, and the plate can be prevented from delaminating, coarse grains and brittle cracking. So as to improve material yield and performance.

-Mechanical heat treatment. The mechanical heat treatment of the niobium alloy is obtained by the "solution treatment → cold deformation → aging" treatment.

Precipitation strengthening to improve the overall performance of the alloy. The mechanical heat treatment process of Nb-10W-1Zr-0.1C alloy is 1650 ℃, 10min → 20%~30% cold deformation → 1420 ℃, 1h.

During the mechanical heat treatment, the solid solution and aging temperature and time and the amount of cold deformation have a great impact on the material properties. These parameters must be reasonably selected and strictly controlled to make the alloy structure uniform, especially the uniform dispersion of the precipitation phase. The alloy has both good high-temperature strength and appropriate room-temperature plasticity, formability, and high-temperature thermal stability.

https://www.etimaterials.org/niobium/https://www.edge-techind.com/category/Niobium-Alloys-54-1.html

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Molybdenum-rare earth oxide alloy

Molybdenum-rare earth oxide alloy (Mo-REO), also called rare earth molybdenum, is an alloy of molybdenum and rare earth element oxides, which is an oxide dispersion-strengthened alloy, similar to rare earth tungsten. Commonly used rare earth element oxides are Y2O3, La2O3, CeO2, and Nd2O3, Sm2O3, Gd2O3, and Sc2O3. They are usually added in the alloy in an amount of 0.5% -3.0% (mass fraction).

The rare earth oxide doped molybdenum is a new material that has been systematically researched since the late 1980s. The addition of rare earth oxides can not only significantly increase the strength of molybdenum, improve the high temperature resistance of molybdenum, but also significantly increase the recrystallization temperature of molybdenum and reduce the brittleness of molybdenum restructure. It is an excellent high temperature structural material. The overall performance is better than the high-temperature molybdenum (Mo-ASK) and TZM molybdenum alloy originally considered to be the best. Rare earth oxide-doped molybdenum is also a new type of electronic functional material-thermionic emission cathode material. Its emission capacity reaches or exceeds the current W-ThO2 materials, which overcomes the radioactive contamination and brittle fracture problems of W-ThO2 materials. As a result, the working temperature of the electric vacuum device is reduced by 150 to 200 ° C. Therefore, rare earth molybdenum as a new type of electronic functional material is attracting increasing attention from material experts and electron tube experts.

In recent years, research on rare earth molybdenum, on the one hand, research on the strengthening mechanism and electron emission mechanism of rare earth oxides on molybdenum, and to clarify the strengthening, toughening and electron emission mechanisms of rare earth oxides, some progress has been made; On the one hand, the research and development of the application of rare earth molybdenum are systematically carried out. For example, Austria's Plansee has successfully developed Mo-Y2O3 foil for special lamps.

The molybdenum-rare earth oxide alloys are classified as follows:

Dispersion strengthened alloy

Unit system: Mo-La2O3, Mo-Y2O3, etc.

Multivariate: Mo-La2O3-Y2O3, Mo-Y2O3-Sc2O3

Precipitation strengthening + dispersion strengthening alloy:

TZM-La2O3, TZM-CeO2, TZM-Y2O3

TZC-CeO2, TZC-La2O3, TZC-Y2O3, TZC-CeO2-Y2O3

ZHM-Y2O3, ZHM-La2O3, ZHM-CeO2

At present, the most important molybdenum-rare-earth oxide alloy is Mo-La2O3, which systematically studies the fracture initiation, high-temperature strength, ductile transition temperature (DBTT), and the properties of the foil. Developed Mo-La2O3 (0.3-1.0%) high temperature resistant molybdenum, which is widely used in high temperature furnaces. This alloy has a higher use temperature than pure molybdenum and higher processability than TZM Molybdenum.