Silicon carbide , 99.9%metalsbasis , 409-21-2

Synonym(s):
;Silicon carbide fibers;Silicon carbide nanowhiskers;Silicon carbide whiskers

CAS NO.：409-21-2

Empirical Formula: CSi

Molecular Weight: 40.1

MDL number: MFCD00049531

EINECS: 206-991-8

PRODUCT Properties

• Melting point: 2700 °C (lit.)
• Density: 3.22 g/mL at 25 °C (lit.)
• bulk density: 0.069g/cm3
• refractive index: 2.6500
• solubility: Soluble in molten sodium hydroxide, potassium hydroxide and in molten iron.
• form: nanopowder
• color: Green
• Specific Gravity: 3.22
• Resistivity: 107–200 (ρ/μΩ.cm)
• Water Solubility: Soluble in molten alkalis (NaOH, KOH) and molten iron. Insoluble in water.
• Hydrolytic Sensitivity: 1: no significant reaction with aqueous systems
• Crystal Structure: Cubic, Sphalerite Structure - Space Group F(-4)3m
• Merck: 14,8492
• Exposure limits: ACGIH: TWA 10 mg/m3; TWA 3 mg/m3; TWA 0.1 fiber/cm3; OSHA: TWA 15 mg/m3; TWA 5 mg/m3; NIOSH: TWA 10 mg/m3; TWA 5 mg/m3
• Stability: Stability
• InChIKey: HBMJWWWQQXIZIP-UHFFFAOYSA-N
• Knoop Microhardness: 3000, at 25°C
• Poissons Ratio: 0.14, sintered
• Shear Modulus: 180 GPa, Calculated
• Modulus of Elasticity: 459 - 476 GPa
• IARC: 2A (Vol. 111) 2017
• NIST Chemistry Reference: Silicon monocarbide(409-21-2)
• EPA Substance Registry System: Silicon carbide (409-21-2)

Description and Uses

Silicon carbide is a hard covalently bonded material predominantly produced by the carbothermal reduction of silica. Silicon carbide is made by heating silica sand and petroleum coke packed around electrodes in an electric resistance furnace to above 2200°C. Depending on the exact reaction conditions the resulting silicon carbide is either a fine powder or a bonded mass that requires crushing and milling to produce a usable feedstock. This material is very resistant to abrasion and to corrosion with a molten slag. It also has excellent resistance to thermal spalling. However as it is a carbide, it will oxidise readily, silicon carbide has a fairly high conductivity.
Several hundred structures of silicon carbide (polytypes) have been identified which have different stacking arrangements for the silicon and carbon atoms. The simplest structure is a diamond structure which is designated /3-SiC. Other structures are either hexagonal or rhombic and are referred to as a-SiC.

Manufacture of abrasives and refractories, brake linings, heating elements, and thermistors.

Safety

• Symbol(GHS): GHS08
• Signal word: Danger
• Hazard statements: H350i
• Precautionary statements: P201-P202-P280-P308+P313-P405-P501
• Hazard Codes: Xi
• Risk Statements: 36/37/38
• Safety Statements: 26-36
• OEB: B
• OEL: TWA: 10 mg/m3 (total)
• WGK Germany: 3
• RTECS: VW0450000
• TSCA: Yes
• HS Code: 28492000
• Hazardous Substances Data: 409-21-2(Hazardous Substances Data)