is silicon carbide ceramic harder than diamond

Silicon carbide ceramic is one of the lightest, hardest, and strongest technical ceramic materials. Additionally, its chemical resistance makes it highly chemical resistant; only boron carbide and diamond can outwit it!Attributes that set it apart: resistance to abrasion, erosion and wear as well as high temperatures; ideal material for refractory linings in industrial furnaces as well as blast nozzles.


Silicon carbide ceramic ranks 9.5 on Mohs hardness scale, making it one of the hardest materials on Earth. Due to this extreme hardness and its ability to be injection molded or extruded into nearly any shape, silicon carbide is highly versatile industrial material. With excellent wear resistance, corrosion protection and toxicological safety properties it makes an excellent choice for use in mechanical seals, bearings and gas sealing rings in harsh environments. Applications also include food processing, chemical production, energy technology and paper manufacturing industries.

Silicon carbide ceramics’ superior high-temperature resistance and thermal shock resistance make them the ideal material for load-bearing applications across a range of industries, from refractories to abrasives. Furthermore, the material exhibits excellent dimensional stability with a high modulus of elasticity for precise performance in load bearing applications. Furthermore, silicon carbide ceramics show exceptional resistance against organic and inorganic chemicals such as phosphoric, sulfuric and nitric acids, making it a long-term material.

Silicon carbide ceramic stands out due to its strength and durability as an ideal refractory material, perfect for use in furnaces and kilns as a lining material or grinding wheel abrasives. Furthermore, its tetrahedral structure holds strong covalent bonds that make the material extremely hard.

Silicon carbide comes into existence through various processes, with recrystallization (RSiC), sintered (SSiC), metal matrix bonding and reaction bonding being among them. Recrystallized silicon carbide (RSIC) is manufactured by firing pure SiC powder with additives in a nitrogen medium at high temperatures, producing RSIC with reduced shrinkage percentage and porosity that provides improved thermal shock resistance as well as high mechanical strength. SSiC is produced by pressing SiC particles into desired shapes and sintering them at high temperatures, producing dense granules with minimal shrinkage percentage. This process makes SSiC an excellent choice for applications requiring high thermal conductivity and superior thermal shock resistance. Sintered granules and RBSC offer very high purity levels, making them suitable for many demanding semiconductor industry applications. Furthermore, these materials boast excellent oxidation resistance making them suitable for applications operating under harsh chemical environments.

Thermal Conductivity

Silicon carbide ceramic is a non-oxide ceramic widely used in thermally and mechanically demanding applications, from motor sports to high strength aerospace engineering. Combining excellent tribological properties of silicon with strength, chemical resistance, low weight and ease of fabrication makes Silicon Carbide the go-to material. Silicon carbide has seen great use in the chemical industry as corrosion-resistant containers and pipelines; an abrasive material in abrasives, shot blasting nozzles and grinding wheels; wear-resistant material for bearings and mechanical seal parts; as well as wear-resistant bearings and mechanical seal parts. Furthermore, silicon carbide has also proven its worth as industrial furnace refractory linings and heating elements; substrates for light emitting diodes; as substrate material for fully ceramic microencapsulated fuels.

Sintered silicon carbide boasts outstanding thermal conductivity, second only to beryllium oxide among technical ceramic materials. It can withstand temperatures of 1400 degrees Celsius without losing hardness and stiffness and is resistant to chemical attack. Furthermore, its very low coefficient of thermal expansion and high chemical inertia make it suitable for use in harsh environments where other ceramics would break down quickly.

Silicon carbide’s superior toughness and abrasion resistance make it the ideal matrix material for hard armour ballistic protection, providing reliable ballistic protection at much reduced weight than comparable armours made of other materials such as aluminium oxide. Thanks to its high modulus of elasticity and compressive strength, silicon carbide absorbs significant amounts of energy during projectile penetration without passing it along to vehicle bodies – thus providing reliable ballistic protection.

Silicon Carbide can be produced either reaction bonded or sintered. Reaction-bonded SiC is produced by infiltrating compacts composed of mixtures of silicon and carbon with liquid silicon; subsequent reactions between silicon and carbon lead to additional SiC being formed which bonds to existing grains of SiC, creating the SiC ceramic. This allows for larger and more complex products than can be created through conventional sintering processes – its flexural strength, fracture toughness and Vickers hardness are often superior compared with reaction bonded materials – while sintered materials often surpass even reaction bonded versions – although depending on grade differences there can be significant variations between products.

Resistance to Corrosion

Corrosion reduces the strength of materials in in-service conditions by losing material as well as creating surface flaws that increase risk of cracking under mechanical stresses.  Crystalline structure of silicon carbide ceramic makes them extremely resistant to corrosion, oxidation, and wear – ideal for applications where other materials would quickly degrade under such conditions.

Silicon Carbide and Silicon Nitride Ceramics’ primary corrosion defense mechanism is their protective oxide layer, which acts as a shield between bulk material and an attacking species. Erosion rates depend upon thermal, mechanical properties of ceramic material as well as environmental variables. Oxygen diffusion from gaseous regions into materials may help replenish its protective oxide layer over time.

Sintered silicon carbide ceramics offer outstanding abrasion and wear resistance as well as corrosion resistance at extreme end-use temperatures, due to their low density, which results in superior mechanical strength for any given weight, and unique ability to retain mechanical properties at elevated temperatures.

Industrial silicon carbide boasts low electrical conductivity; however, this is more than made up for by its outstanding chemical, mechanical, optical and hardness/wear resistance properties. As a result, silicon carbide makes an excellent material choice for applications including cutting, grinding, drilling and milling across various industries.

Foamed silicon carbide (FSC) features a special space network structure which greatly increases its specific surface area, selective permeability to liquid and gas media, energy absorption capacity, heat transfer coefficient and pressure resistance properties – making FSC an attractive material in fields as diverse as metallurgy, chemical industry transportation machinery national defense environmental protection.

we offer all of the primary types of sintered silicon carbide, from standard SiSiC to reaction bonded and sintered silicon carbide – siliconized products (SSiC). Each can be produced to tight dimensional tolerances with superior load-bearing capacity at elevated temperatures – making them suitable for ballistic armor components that must ensure maximum range and lethality against current and emerging threat levels.

Wear Resistance

Silicon carbide is one of the hardest and lightest ceramic materials. With its very high modulus of elasticity and excellent dimensional stability, this material boasts great wear resistance while being highly chemical-resistant even at temperatures exceeding several hundred degrees Celsius – not to mention impact and shock resistance that makes it perfect for mechanical seals, bearings, gas sealing rings in harsh or even explosive environments.

silicon carbide ceramic can provide significant protection from corrosion and erosion in many applications where other refractories cannot, such as wear-resistant linings for applications where temperatures up to 1400 degrees Celsius exist for extended periods. Furthermore, its resistance to oxidation makes it particularly effective against corrosion-based corrosion applications and abrasive environments.

There are various kinds of silicon carbide ceramic, with each type having different manufacturing processes that lead to different porosities and densities. Reaction bonded silicon carbide is formed using porous carbon feedstock and molten silicon using additive forming techniques such as dry pressing or extrusion, and sintered at extremely high temperatures to produce an extremely dense structure with superior chemical and mechanical properties for extreme end-use environments. Sintered silicon carbide offers higher purity, greater mechanical strength, and superior corrosion resistance (in particular hydrofluoric acid corrosion resistance).

Foamed SiC ceramics feature uniform pores with low relative densities and large specific surface areas, offering low relative densities as well as selective permeability to liquid and gas media, making it suitable for applications in metallurgy, chemical industry, energy electronics transport machinery national defense environmental protection biology applications.

Industrial-grade nitrided silicon carbide is widely utilized for plant components that must withstand severe abrasive wear or temperature variations, such as coal dust distributors, coke ramps and cyclone liners. Because of its superior resistance to erosion and wear it can outlive traditional lining materials like glass, basalt or hard facings. Furthermore, it is ideal for prolonging the lifetime of pipes frequently exposed to such conditions.