silicon carbide whisker – Silver Nanoparticles Antimicrobial,Copper Oxide Nanoparticles,Gold Nanopowder

March 13, 2024

Silicon carbide whiskers can significantly improve the service life of resin diamond grinding wheels

The diamond grinding wheel uses diamond abrasive as raw material, and uses metal powder, resin powder, ceramics and electroplated metal as binders respectively. The circular bonded abrasive tool with a through hole in the center is called diamond grinding wheel (alloy grinding wheel).

The resin-bonded diamond grinding wheel generally has a low life and cannot meet the requirements of advanced numerical control machine tools. The short life is mainly due to the poor wear resistance of the resin bond itself or the low holding force on the diamond, which causes the diamond abrasive particles to fall off prematurely during the grinding process. Therefore, how to improve the wear resistance of the resin bond and improve the holding force of the resin on the diamond has become the key to improving the service life of the resin bond diamond grinding wheel.

The addition of silicon carbide whiskers can greatly improve the strength, hardness, heat resistance, polishing, etc. of the bond and the grinding wheel. Silicon carbide whiskers have unique mechanical and physicochemical properties such as high hardness, high strength (toughness), and excellent wear resistance, so they are widely used in metals, ceramics, plastics, etc.

Strengthening and toughening of materials and composite materials to improve the strength of composite materials and prevent shrinkage and deformation. The shape of silicon carbide whiskers is like needles, especially its Webster hardness is close to diamond and has good toughness and wear resistance, and compared with abrasive grains, even if the diameter is the same as the grain size of abrasive grains, there are whiskers of a certain length that are combined with The agent has a relatively large bonding area and bonding strength, which greatly improves the service life of the grinding wheel.

The β-type micron-sized silicon carbide whiskers produced by Hongwu Nano have the characteristics of high purity and good morphology, and are the preferred materials for strengthening and toughening of various metal-based, ceramic-based and resin-based composite materials. Its strengthening and toughening effect and scope of application are unmatched by other materials.

Beta silicon carbide whiskers are needle-like single crystals. As an atomic crystal, it has low density, high melting point, high strength, high modulus, low thermal expansion rate, and excellent characteristics such as wear resistance, corrosion resistance, high temperature resistance, oxidation resistance, etc. It is mainly used for metal base, ceramic base , Reinforcement and toughening of resin-based composite materials, significantly improve the properties of composite materials.

Its main physical performance indicators are as follows:
Whisker diameter Diameter: 0.1-2.5um
Whisker Length: 10-50um
Density: 3.2g/cm2
Hardness: 9.5 Mobs
Modulus Modulus: 480GPa
Tensile Strength Strength of extension: 20.8Gpa
Tolerable temperature: 2960℃

March 31, 2016

Inorganic non-metallic materials and metal materials and organic polymer materials

1. Introduction
Usually it refers to as the main inorganic glass, ceramics, graphite, rock as well as organic as the main wood, plastic, rubber and other similar materials. Composed by a crystalline or amorphous. No metallic luster. It is a poor conductor of heat and electricity (except carbon). The poor mechanical properties of metallic materials in general
(Except glass and steel), but some non-metallic materials can replace metal materials, chemical industry indispensable material.
Inorganic non-metallic materials and metal materials and organic polymer materials, is a complete modern material system is an important component.
2. Classification
Non-metallic materials and inorganic materials can be divided into two major categories of organic material. In mechanical engineering, there are many varieties of the more commonly used.
① belong refractory inorganic materials, ceramics, abrasives, carbon and graphite materials, such as asbestos;
② belong to organic materials include wood, leather, adhesives and polymer composite materials ── synthetic rubber, synthetic resin, synthetic fiber;
③ non-metallic fiber-reinforced composite material composed of a resin base.
3. the inorganic material
Inorganic non-metallic materials and metal materials and organic polymer materials, is an important part of contemporary full material System
Minute. Certain elements of an oxide, carbide, nitride, boride, sulfur-based compounds (including sulfides, selenides and tellurides) and silicates, titanates, aluminates, phosphates oxyacid salt inorganic material mainly composed of Pan said. Including ceramics, glass, cement, refractories, ceramics, abrasives and new inorganic materials. Wherein the ceramic word, and ceramics with a similar inorganic material emerging, its extension of the concept is also expanding. In the broadest sense and meaning of ceramic concept almost identical inorganic non-metallic materials.
Production Process Classification
Into ceramics, glass, cement, refractories, ceramics, carbon materials and other categories, while new materials according to their production processes, use and development, and gradually form a number of new classes of materials, such as inorganic composite materials, inorganic porous material . Some species are incorporated by customary traditional categories, such as: ferroelectric, piezoelectric ceramics are incorporated; crystallite glass, fiber optics and other incorporated into the glass.
The main component of classification
Some also in accordance with the main component material classification, silicates, aluminates, titanates, phosphates, oxides, nitrides, carbides materials; according to the material of zoning, there are daily, construction , chemicals, electronics, aerospace, communications, biotechnology, medical materials.
Material properties Classification
Depending on the material properties of points, there are gelling, fire-resistant, heat insulation, wear resistance, electrical conductivity, insulation, corrosion resistance, semiconductor materials; physical state of the material according to points, there are crystal (monocrystalline, polycrystalline, microcrystalline), non- Crystal and composite materials, but also from the appearance of the sub-form material, there are massive, porous, fibers, whiskers, thin film materials.
4. Features
High strength, hardness, high temperature and corrosion resistance. In addition, the cement in the cementitious properties, the optical properties of glass, ceramics on the corrosion resistance, dielectric properties, heat-resistant refractory material in the insulation performance has its excellent characteristics, metal materials and polymer materials less . However, compared with the metal material, breaking it low intensity, the lack of ductility, are brittle materials. Compared with polymer materials, high density, the manufacturing process is more complex. Special Features inorganic non-metallic materials are:
① different features, such as: high temperature anti-oxidation characteristics such as high temperature oxide; alumina, beryllium oxide ceramic high-frequency insulation characteristics; ferrite magnetic properties; a light transmission properties of the optical fiber; diamond, cubic boron nitride The TodayHot} superhard properties; conductive properties conductive material; fast hard early strength cement rapid coagulation, rapid-hardening properties and the like.
② various physical effects and microscopic phenomena, such as: light-sensitive material – electrical, thermal material heat – electricity, power piezoelectric material – electricity, gas sensing materials – the electricity, humidity of materials humidity – electricity and other material for functional physical and chemical parameters of the conversion characteristics between.
③ different nature of the composite material is constituted by a composite material, such as: metal ceramics, high temperature inorganic coatings and inorganic fibers, SiC whiskers, etc. reinforced material.

August 12, 2015

An Introduction of Silicon Carbide Whisker

Silicon carbide whiskers is a little flawed, there is a certain aspect ratio of single crystal fibers, it has a very good temperature resistance and high strength. Mainly used for applications requiring high temperature high-strength material toughening occasions. Such as: aerospace materials, high-speed cutting tool. Currently, with high cost performance.

Silicon carbide whisker belong to a diamond crystal, is now synthesized whiskers highest hardness, modulus maximum, maximum tensile strength, heat resistance temperature of the highest whiskers products, divided the α type and β type two forms, which is superior to α-type β-type and has a higher hardness (Mohs hardness of 9.5 and above), better toughness and conductivity, wear resistance, high temperature, particularly resistant to earthquake , corrosion resistance, radiation has been applied on and engine, high-temperature turbine rotor, special parts on aircraft, missiles shell.

Cubic silicon carbide whisker whiskers, and belong to a diamond crystal, is now synthesized whiskers highest hardness, modulus maximum, maximum tensile strength, heat resistance temperature of the highest whiskers products, divided the α type and β type in two forms, including β-type performance than α type. β type than the α type having a higher hardness (Mohs hardness of 9.5 and above), better toughness and conductivity, wear resistance, high temperature, especially earthquake-resistant, corrosion-resistant, resistant to radiation, have housing in aircraft, missiles on and engine, high-temperature turbine rotor, has been applied on special parts.

Silicon carbide is extremely anisotropic crystal growth is achieved by a catalyst on the basis of silicon carbide particles on the surface along the crystal growth of the short fibers, there are two main methods currently producing a gas phase reaction method and a solid material, which method is more solid material It is economical and suitable for industrial production.

Japan and the United States show the synthesis of silicon carbide of a high enthusiasm, in terms of reducing costs and improving the quality of work done a lot of research. Ramsey and other American to amorphous silica as silicon source rice husk species (obtained from burning carbonized rice husk), were mixed in pulverized petroleum coke carbonized rice husk and powder sintering to produce a silicon carbide products. Japan Tanaka and other acid-boiled rice husk, cleaning, carbonation, sintering and other steps to obtain high-purity silicon carbide products.

The first production of silicon carbide whiskers of manufacturers, production of silicon carbide whiskers is a high strength beard shape (one-dimensional) single crystal, high strength, high modulus, and many other excellent mechanical properties, it is widely used in metal matrix, ceramic matrix composite. Mainly used in ceramic cutting tools, high temperature components in the field of aerospace, main bearing strong, large mud pumps, etc. Add to this new material has obtained a more excellent high temperature components, wear resistance, widely used as a structural material in aviation, aerospace, automotive, machinery, petrochemical and other, known as the king of whiskers said. In particular, it has a special significance in the automotive, aerospace engines, housing and so on.

In addition, it was added as an enhanced component plastic matrix, metal matrix or ceramic matrix and play a role in enhancing toughening, high thermal conductivity Sic use of nano materials, high insulation resistance, as large scale integrated circuit substrates in the electronics industry and packaging materials. As an optical material information in the television show, fields of modern communications and the Internet with a high value.

Silicon carbide whiskers in the manufacture of high-strength plastic, metal and ceramic applications work, you can speed up the upgrading of key traditional products. As the nano-silicon carbide whiskers of outstanding features, it has a special role in the aerospace industry industry sectors, namely in aircraft, missile applications and engine housing, the high temperature turbine rotor, special components, military industry and so it huge demand for civilian industry.

May 26, 2015

Types of Chemical Heater and Silicon Carbide Whisker

Silicon Carbide is the only chemical compound of carbon and silicon. It was originally produced by a high temperature electro-chemical reaction of sand and carbon. Silicon carbide is an excellent abrasive and has been produced and made into grinding wheels and other abrasive products for over one hundred years. Today the material has been developed into a high quality technical grade ceramic with very good mechanical properties.It is used in abrasives,refractories,ceramics,and numerous high-performance applications. Silicon carbide whisker can also be made an electrical conductor and has applications in resistance heating, flame igniters and electronic components. Structural and wear applications are constantly developing.

Chemical heater and etch process are important terms that must be learned by people and businesses in the semiconductor industry. In this article, I am sharing about the types of chemical heaters used in the wet process system as well as the silicon nitride etch process.

Types of chemical heater

Quartz – Gas Heater — a system that is designed to meet the growing demand for heated high purity gasses. It has the capacity of heating a wide range of gases including: Ammonia (NH3), Helium (He), Argon (Ar), Hydrogen (H2), Arsine (AsH3),Hydrogen Bromide (HBr), Boron Trichloride (BCl3),Hydrogen Chloride (HCl), Carbon Dioxide (CO2), Nitrogen (N2),Carbon Monoxide (CO), Chlorine (Cl2), Nitrous Oxide (N2O), Oxygen (O2),Disilane (Si2H6), Sulfur Dioxide (SO2),Methylsilane (SiH3CH3)

Quartz – Fluid Heater — used in the semiconductor industry and its traditional application includes recirculation loop, either as the sole head source or a combination of a heated quartz tank.

SiC – HF & KOH Heater — designed for heating HF (hydrofluoric acide), KOH (potassium hydroxide), and other high PH chemistries. It uses high purity Silicon Carbide (SiC) as a heat transfer material because it has excellent heat transfer properties and eliminates the risk of contamination due to Teflon breakdown.
Interesting Facts about the Silicon Nitride Etch process

To be able to achieve the greatest etch rates and best selectivity, the phosphoric acid should have the highest ratio of water at a given temperature. For as long as the boil point is maintained, the etch rate of both Si3N4 and SiO2 can be precisely controlled.

Maintaining a boiling solution is one of the challenges in the etch process. When phosphoric acid is heated, the water solution begins boiling off. When temperature is not maintained, it affects the etching process as the acid concentration increase. Wet etch companies use a standard temperature controller to maintain temperature, but the water concentration will decrease and will change the etch rates. As a solution, wet etch process engineers use water addition system.

A technology called closed “reflux” system is used and it is created above the bath using condensing collar and a lid – this is to minimize water addition.

The chemical fumes and high temperatures that Nitride Etch tanks are subjected to are known to decrease bath life substantially by attacking the sealant that prevents liquid and fumes from entering the heater area. This problem has been addressed through the use of aquaseal.

Quartz Nitride Reflux system is engineered to address the unique needs of the silicon nitride etch process. It gives the following benefits to customers: process uniformity, lot-to-lot repeatability, prevents stratification.