Silicon Carbide (SiC)
Silicon carbide (SiC) is a synthetic, semiconducting fine ceramic that excels in a wide cross-section of industrial markets. Manufacturers benefit from an eclectic offering of silicon carbide grades due to the availability of both high-density and open porous structures. Combined with the material’s outstanding high-temperature strength and thermal shock resistance, alongside inherently impressive mechanical properties, silicon carbide is one of the most versatile refractory ceramics worldwide.
Silicon Carbide: Grades, Formats & Bonding Types
Saint-Gobain has spent years developing a uniquely broad understanding of the thermomechanical and chemical properties of silicon carbide ceramics developed via numerous distinct manufacturing avenues. As a result, Saint-Gobain has now positioned itself as one of the foremost silicon carbide ceramic suppliers worldwide. With a selection of industry-trusted products on offer, Saint-Gobain routinely services demanding application areas with uniquely tailored solutions.
Sintered Silicon Carbide SiSiC, like Saint-Gobain’s proprietary Hexoloy® brand, is produced at extremely high temperatures (~2,000°C) in inert atmospheres using a range of forming methodologies, including dry-pressing and extrusion. Reaction bonded, or siliconized, silicon carbide is formed using a porous carbon feedstock and molten silicon via additive forming, casting or extrusion. Each of these fully-densified silicon carbide ceramics achieves exceptional chemical and mechanical properties in extreme end-use temperatures exceeding 1,400°C (2,552°F).
Our brands based on Sintered Silicon Carbide:
Reaction bonded, or siliconized, is formed using a porous carbon feedstock and molten silicon via additive forming, casting or extrusion. Each of these fully-densified silicon carbide ceramics achieves exceptional chemical and mechanical properties in extreme end-use temperatures exceeding 1,400°C (2,552°F).
How do we make Hexoloy® ceramic material?
Economical forming is determined by volume and tolerances of the final part. Dry pressing to size is the most economical forming method for volumes of 300 pieces or more, which help to justify the initial expense of tooling designed specifically for each part. Isostatic pressing is suited to low volumes and prototype items.
Pre-Sinter (Green) Machining
Machining in the pre-sintered, or green, state is often desirable because it allows manufacturing of finished shapes without expensive grinding of sintered material. Green machining is accomplished using conventional processes. Stock removal can be accomplished 15 times faster in the green state than in the sintered state. Green machining provides parts to tolerances of 0.5 percent to 1.0 percent of their final dimensions. Typical green machined surface finishes range around 32 to 64 microinches.
Grinding / Finishing
Precision grinding capabilities have been developed to meet the exacting specification requirements requested by the automotive, aerospace and nuclear industries. Saint-Gobain has the expertise to grind to close tolerances on most shapes (.0005"). Typical ground parts hold finishes of 16 or better microinches. When surface finishes are critical to improve friction and wear performance, finsihing operations can improve surfaces up to 4 microinches providing surface flatnesses to one helium light band.
Our company mission is to maintain the highest level of quality for our customers. Saint-Gobain has state-of-the-art nondestructive evaluation equipment for final quality inspections of internal structures. These include bulk and surface wave ultrasonics, fluorescent dye penetrant, radiography, acoustic emission and photomicrography.
Saint-Gobain Performance Ceramics & Refractories is a world-leader in the delivery of innovative, reliable and consistent ceramics for composite armor systems. The company specializes in high-performance, lightweight ceramic materials designed to protect against current and emerging ballistic threats.