How to solve the problem of sintering cracks in silicon carbide ceramics? - VeTek semiconductor

In the field of modern industrial manufacturing, high-performance ceramic materials have gradually become the preferred materials for key industrial applications due to their excellent wear resistance, high temperature resistance and chemical stability. High-purity silicon carbide (SiC) ceramics have become an ideal choice for many industrial fields due to their unique physical and chemical properties, such as high strength, high hardness and good thermal conductivity. However, in the preparation process of silicon carbide ceramics, the problem of sintering cracks has always been a bottleneck restricting its performance improvement. This article will deeply explore the performance problems of sintering cracks in high-performance and high-purity silicon carbide ceramics and propose solutions.

Ⅰ. Application background of high-performance silicon carbide ceramics

Silicon carbide ceramics have broad application prospects in aerospace, automotive industry, energy equipment and other fields. In the aerospace field, silicon carbide ceramics are used to manufacture turbine blades and combustion chambers to withstand extreme high temperatures and oxidizing environments. In the automotive industry, silicon carbide ceramics can be used to manufacture turbocharger rotors to achieve higher speeds and durability. In energy equipment, silicon carbide ceramics are widely used in key components of nuclear reactors and fossil fuel power plants to improve the operating efficiency and safety of equipment.

Ⅱ. Causes of sintering cracks in silicon carbide ceramics

Silicon carbide ceramics are prone to cracks during the sintering process. The main reasons include the following aspects:

Powder properties: The particle size, specific surface area and purity of silicon carbide powder directly affect the sintering process. High-purity, fine-particle silicon carbide powder is more likely to produce a uniform microstructure during the sintering process, reducing the occurrence of cracks.

Molding pressure: Molding pressure has a significant effect on the density and uniformity of the silicon carbide blank. Too high or too low molding pressure may cause stress concentration inside the blank, increasing the risk of cracks.

Sintering temperature and time: The sintering temperature of silicon carbide ceramics is usually between 2000°C and 2400°C, and the insulation time is also long. Unreasonable sintering temperature and time control will lead to abnormal grain growth and uneven stress, thereby causing cracks.

Heating rate and cooling rate: Rapid heating and cooling will produce thermal stress inside the blank, leading to the formation of cracks. Reasonable control of heating and cooling rates is the key to preventing cracks.

Ⅲ. Methods to improve the sintering crack performance of silicon carbide ceramics

In order to solve the problem of sintering cracks in silicon carbide ceramics, the following methods can be adopted:

Powder pretreatment: Optimize the particle size distribution and specific surface area of silicon carbide powder through processes such as spray drying and ball milling to improve the sintering activity of powder.

Forming process optimization: Use advanced forming technologies such as isostatic pressing and slip forming to improve the uniformity and density of the blank and reduce internal stress concentration.

Sintering process control: Optimize the sintering curve, select the appropriate sintering temperature and holding time, and control grain growth and stress distribution. At the same time, adopt processes such as segmented sintering and hot isostatic pressing (HIP) to further reduce the occurrence of cracks.

Adding additives: Adding appropriate amounts of rare earth elements or oxide additives, such as yttrium oxide, aluminum oxide, etc., can promote sintering densification and improve the material's crack resistance.

Ⅳ. About VeTek Semiconductor Silicon Carbide Ceramics

VeTek Semiconductor is a leading manufacturer and supplier of Silicon Carbide Ceramics products in China. With our extensive portfolio of semiconductor-grade Silicon Carbide Ceramics material combinations, component manufacturing capabilities, and application engineering services, we can help you overcome significant challenges. Our main Silicon Carbide Ceramics products include SiC Process Tube, Silicon Carbide Wafer Boat for Horizontal Furnace, Silicon Carbide Cantilever Paddle, SiC Coated Silicon Carbide Wafer Boat and High Pure Silicon Carbide Wafer Carrier. VeTek Semiconductor's ultra-pure Silicon Carbide Ceramics are frequently used throughout the entire cycle of semiconductor manufacturing and processing.VeTek Semiconductor is your innovative partner in the field of semiconductor processing.