High-performance electronic systems demand components with the perfect balance of compact size and long-term reliability, particularly where physical wear may be an issue. This is especially pertinent to applications where wear-and-tear is an issue. Silicon Carbide, commonly referred to as Carborundum, is one of the more unique technical ceramic materials. Unlike most technical ceramics, it boasts relatively high strength and hardness for increased abrasive and grinding wheel use, as well as being used refractorily and mechanical seal parts. It has been in use for more than 100 years in these capacities alone!
Silicon Carbide ceramic is one of the lightest and hardest advanced ceramic materials currently available, boasting mechanical properties that remain constant up to 1400 degrees Celsius. Furthermore, SiC boasts great thermal conductivity properties while being acid resistant and having low thermal expansion – making it an ideal material to use in challenging environments.
SiC is the hardest material that can be cast as either an ingot or crystal. Produced through electrochemical reaction between silica and carbon in electric resistance furnaces, SiC granules can then be ground down into powder for use in grinding wheels and other abrasives. Mass-production has taken place both as powder and single crystal for over 100 years – producing SiC for use as grinding wheels and other abrasives; SiC also outshines diamond and boron carbide in terms of hardness – while producing other products through either sintering or melting processes.
Elkem employs a patented process for mixing and classifying high-grade SiC, then packaging it according to customer specifications in our state-of-the-art facility, Elkem Processing Services (EPS). DuraShock, our tough and hard Boron-Silicon Carbide ceramic composite, provides outstanding ballistic protection at significantly less product weight than armoured steel or aluminium oxide armouring solutions; thus resulting in lower fuel consumption and range while still achieving excellent ballistic performance with significant environmental and cost benefits – offering significant environmental and economic advantages over alternatives such as armoured steel or aluminium oxide armoring solutions. This offer significant environmental and cost advantages over their steel counterparts
Thermal shock resistance
Silicon carbide, commonly referred to as Carborundum, has become an extremely durable chemical compound created from bonding silicon and carbon. While Moissanite occurs naturally as a gemstone form of silicon carbide, most often seen is powder form used for sintering into tough ceramic materials that have many applications such as sandpaper, grinding wheels and cutting tools – as well as wear parts in pumps, rocket engines, semiconductor substrates of light-emitting diodes etc.
Thermal shock resistance of ceramic materials refers to their ability to tolerate sudden temperature changes without cracking, shattering or otherwise becoming damaged. This property is achieved through various means including low coefficient of expansion and high heat endurance. Certain ceramics such as fused silica and cordierite possess excellent thermal shock resistance while others, like silicon nitrides and silicon oxycarbide exhibit poor results in this regard.
Resistance to oxidation
Silicon Carbide ceramic boasts excellent resistance to oxidation, making them the perfect material for use in chemical industry and process engineering applications. Their exceptional resistance allows them to effectively separate corrosive liquids and gases from carrier gases while also recovering heat in cases where chemical reactions produce high process temperatures and large concentrations of acids or alkalis.
Due to their excellent mechanical properties – including high Vickers hardness and fracture toughness; high thermal conductivity; and low thermal expansion rates. They are also resistant to acid and lye-based environments.
Not to be confused with natural moissanite, which can only be found in very minute quantities in meteorite deposits and corundum deposits such as kimberlite, all silicon carbide sold commercially is synthetically produced through pressure sintering powdered silicon carbide with aluminium oxide-based ceramic components to form dense material that has virtually no pores and high strength and fracture toughness.
Boron carbide ceramics (B4C) are produced similarly to SiC. Sub-micron B4C powder is sintered at temperatures over 2,000degC without pressure (SSIC) or under high temperatures and pressure (HPBC or HIPBC), producing ceramics characterised by high Vickers hardness, excellent fracture toughness and chemical stability and resistance to oxidation at elevated temperatures – characteristics shared with SiC ceramics.
Resistance to wear
Silicon Carbide ceramic is one of the lightest and hardest advanced ceramic materials, boasting outstanding corrosion resistance, chemical stability, and thermal expansion properties that make it suitable for applications in dynamic sealing technology, pump and drive systems, chemical industry process engineering as well as dynamic sealing technology for dynamic sealing applications. When compared with metals, silicon carbide components offer several times greater wear resistance due to their low coefficient of friction and wear resistance properties.
Silicon carbide has long been used as an abrasive and material for industrial furnaces since its introduction in the late 19th century. Furthermore, silicon carbide serves as a raw material for sandpaper production as well as grinding wheels, cutting tools, sandpaper and cutting tools – as well as being an excellent substrate for light emitting diodes (LEDs). Although silicon carbide only occurs naturally as moissanite crystals, since late 19th century large-scale production of powdered and crystal forms has taken place to meet demand.
Reaction bonding and sintering are the two methods for producing silicon carbide ceramics, each of which affects its final microstructure differently. Reaction bonded SiC is made by infiltrating compacts made up of mixtures of SiC and carbon with liquid silicon before reacting it with carbon through chemical reactions before being sintered into shape. Regardless of which approach is taken to produce SiC, both variants offer exceptional performance with excellent resistance to erosion, wear resistance, low CTE values and strong acid resistance characteristics that make them excellent choices for spray nozzles, shot blast nozzles and cyclone components among many others.