SiC (Silicon Carbide) Ceramics

SiC Ceramics, or Silicon Carbide Ceramics, is a class of synthetically engineered fine ceramic materials majorly consisting of silicon carbide, renowned for their prominent holistic properties. The mechanical merits of silicon carbide include small weights, unparalleled hardness, excellent frictional wear resistance, and mechanical resilience. The thermal and chemical characteristics of silicon carbide ceramic are also remarkable, spanning from high-temperature strength, thermal shock resistance, low thermal expansion, and corrosion resistance. Besides, its large breakdown electric field strength and wide bandgap made silicon carbide advantageous as a semiconductor material. 

Through processes such as hot pressing or sintering, SiC ceramics are crafted to meet the demands of diverse applications including semiconductor, automobile, construction and chemical industries, environmental protection, space, satellite, information electronics, etc. For example, the lightweight, high stiffness, and low thermal expansion features predestine SiC ceramics’ usage as the material for space telescope mirrors. The inertia of acids and alkalis made silicon carbide ceramic reliable for applications sensitive to chemicals, such as heat exchanger plates. With its good resistance to oxidation and corrosion as well as resistance to temperature changes, this ceramic is also used as a component for refractory applications: burner nozzles, jets, and flame tubes. Another common application for SiC is dynamic sealing utilizing friction bearings and mechanical seals where silicon carbide ceramic offers a far more affordable choice with extended tool life when handling aggressive, high-temperature media.

SiSiC (silicon infiltrated silicon carbide, also called siliconized SiC, reaction bonded silicon carbide/RB sic) is a subcategory of the class of silicon carbide ceramics consisting of SiC particles in a matrix of excess silicon, besides the common virtues of SiC ceramics as mentioned above such as lightweight, weight endurance, etc. SiSiC also stands out with the appealing attributes of ease of forming complex shapes with tight tolerances, and resistance to corrosion, oxidation, and high temperatures, making them suitable for manufacturing complex large-volume components and a broad range of applications such as furnace/kiln components, tribological uses/wear components, seals, nozzles. Shalom EO offers silicon-infiltrated silicon carbide manufactured using a combination of gel casting and reaction bonding techniques. Gel casting is a near-net-shape forming method for the preparation of ceramic parts with large sizes and/or complex shapes at low cost. And reaction bonding is a manufacturing process a chemical reaction between porous carbon or graphite with molten silicon. Utilizing industrial-leading research results, our state-of-the-art fabrication techniques ensure the provision of high-quality  silicon carbide ceramics with the following technical advantages:

1. Near-net-size molding: The product exhibits minimal shrinkage (less than 1%) during the reaction bonding process. This enhances the yield of SiC ceramics with intricate shapes, enabling high-precision manufacturing.

2. Realization of complex structures: Various complex shapes including semi-closed backs and hollow structures can be achieved, reducing overall weight and accommodating a wider range of application needs.

3. Excellent green body machinability: The intermediate green body processing stage can be efficiently completed using CNC machining, achieving an accuracy of 0.1mm at best. This significantly reduces the finishing cycle of the sintered body, enhancing efficiency and lowering costs.

4. Superior optical machinability: After optical processing (such as milling, and polishing), the surface roughness can be improved to better than 3nm, obtaining high-quality finishes.

Besides, as shown in the comparison chart below, compared to other material, Shalom EO's fine SiC Ceramics have excellent specific stiffness (almost four times the magnitude of ULE materials) and thermal stability (almost four times the magnitude of Be materials), it is also resistant to space radiation and proton oxygen. The material is also environment-friendly.

Comparison Chart of Shalom EO's Silicon Carbide Ceramics and Other Common Counterpart Materials

These properties ensure that the precision SiC ceramics provide reliable performance for demanding applications. As core materials or components, our SiC ceramics show great market prospects in equipment manufacturing including photoelectricity equipment, precise instruments, high-speed railway equipment, and new energy vehicles. We have also succeeded in developing an ultra-large size 4.03m SiC mirror.

Hangzhou Shalom EO offers RB SiC ceramics tailored to customers' requests. Besides, we also provide various ceramic components and parts, including SiC Mirrors (including Ultra-large-aperture Mirrors, Galvo Scanning Mirrors, Scanning mirrors, and Fast Steering Mirror), Silicon Carbide Structural Components (Monolithic SiC Ceramic Frames, Mounting Substrates, etc.), and Precision Silicon Carbide Chucks & Substrates for Semiconductors, Integrated Circuits/IGT. 

The features of these SiC ceramic-based products are listed below:

1）SiC Ceramic Mirrors: 

-Applications: For advanced optoelectric systems

a) Ultra-lightweight: 

• Back rib thickness 1-3mm
• Hollow structure further reduces weight
• Weight reduction rate up to 90%
• Minimum surface density better than 10kg/m^2

b) Complex Structure SiC Ceramic Mirrors： 

• Hollow structure to reduce the weight of mirror blanks
• Backside semi-closed with structure to improve the rigidity of mirror blanks 
• Optical-mechanical integrated construction to reduce the weight of the system, ameliorate the thermal mismatch, and enhance the environmental adaptability

c) Galvo Scanning Mirrors, Scanning Mirrors, Fast Steering Silicon Carbide Mirrors: 

• Low rotational moment of inertia
• High resonance frequency
• High thermal stability
• Non-toxic (a fine substitute for Be)

2）Silicon Carbide Structural Components

-Applications: For precision integrated silicon carbide frames, mounting substrates and other types of structural components, used in sophisticated optoelectric systems, semiconductor manufacturing equipment and other fields

3）Precision SiC Ceramic Chucks and SiC Ceramics Substrates

-Applications: For semiconductor manufacturing equipment, integrated circuits/IGBT and substrates of other devices

Densified and homogeneous material quality, good machinability

High surface precision and high form precision can be obtained

Air flues, runners inside the SiC ceramic components available