Wolframkarbid

Wolframkarbid, or tungsten carbide (WC), is a chemical compound composed of tungsten and carbon. It is a hard, refractory ceramic material with a hexagonal crystal structure. Tungsten carbide occurs in powder form and as cemented carbide when bound with a metal such as cobalt, nickel, or iron, creating materials used for cutting tools and wear parts.

Key properties include exceptional hardness, a very high melting point around 2870°C, a high density of about 15.6 g/cm3, and high stiffness. It retains hardness at elevated temperatures (hot hardness) and exhibits strong wear resistance. In contrast to many metals, WC is brittle, and its toughness can be enhanced by using a metallic binder in cemented carbide forms.

Production and forms: Pure WC is produced by carburizing tungsten or tungsten oxide with carbon at high temperatures, or by carburizing tungsten compounds. In industry, WC powder is mixed with a binder (commonly cobalt) and sintered to form cemented carbide tools and components. The particle size and binder content determine properties such as toughness and fracture resistance.

Applications: Tungsten carbide is widely used for cutting, milling, drilling, and turning tools, wear-resistant coatings and parts in mining, oil and gas, and forming dies. It is also used in dental and medical tooling and precision instrumentation due to its hardness and wear resistance.

Safety and environmental aspects: Tungsten carbide dust can be hazardous if inhaled; cobalt binders pose health risks. Proper ventilation, dust control, and protective equipment are essential during processing. WC products are generally stable, but machining and grinding can release fine particles.