What is Pressureless Sintered Silicon Carbide?
Pressureless sintered silicon carbide ceramics are high purity, ultra-fine silicon carbide powder as raw materials, adding a small amount of sintering additives, such as boron, carbon, etc., in atmospheric pressure inert gas or vacuum atmosphere, sintering at high temperature from 1950 to 2100℃, Very strong sintering bonds between the material grains are formed,the product is almost completely dense, with excellent mechanical properties of ceramic materials.Direct Sintered SiC is a better grade than Reaction Bonded SiC and is commonly specified for high-temperature work and hard-faced seal components.
The technics summary of Pressureless sintered silicon carbide ceramics
1.Principle of non-pressure sintering
Pressureless sintering is a process that high temperature causes material transfer and diffusion between powder particles to achieve densification without external pressure.
2.To choose High purity silicon carbide powder
High-purity silicon carbide powder is usually used as raw material. These powders have lower impurity levels to improve the performance of the final product. Thus it ensures high-quality silicon carbide ceramics products.
3.Control of sintering temperature and time
It is important for achieving high density and excellent properties of silicon carbide ceramics to make sure appropriate sintering temperature and time .Too high or too low temperature and too long or too short time may affect the quality of the material.
Unique advantages of Pressureless sintered silicon carbide ceramics
The silicon carbide product obtained by non-pressure sintering is almost completely dense and has excellent mechanical properties. One advantage of this process is that it allows the use of various molding methods to produce products with different shapes, and the application of appropriate additives can bring high strength and toughness.
1.Performance retention at high temperatures. Even at extremely high temperatures, press-free sintering of high-purity silicon carbide ceramics can maintain the stability of its structure and properties, which makes it have great potential in high-temperature applications.
2.Oxidation resistance.In addition to high temperature stability, this material also has good oxidation resistance and is able to work stably in oxidizing environments for long periods of time without significant degradation.
3.High density.Pressureless sintering technology can densify sic powder under high temperature and high pressure to form a dense structure. This property significantly improves the mechanical strength and wear resistance of the material.
4.Excellent mechanical properties
