The Extraordinary Properties & Benefits of Tungsten Carbide
Strength - Tungsten carbide has very high strength for a material so hard and rigid. Compressive strength is higher than virtually all melted and cast or forged metals and alloys.Rigidity - Tungsten carbide compositions range from two to three times as rigid as steel and four to six times as rigid as cast iron and brass. Young's Modulus is up to 94,800,000 psi.
Heat Resistance - High resistance to deformation and deflection is very valuable in those many applications where a combination of minimum deflection and good ultimate strength merits first consideration. These include spindles for precision grinding and rolls for strip or sheet metal.
Impact Resistant - For such a hard material with very high rigidity, the impact resistance is high. It is in the range of hardened tool steels of lower hardness and compressive strength.
Heat and oxidation resistance - Tungsten-base carbides perform well up to about 1000°F in oxidizing atmospheres and to 1500°F in non-oxidizing atmospheres
Low temperature resistance (cryogenic properties) - Tungsten carbide retains toughness and impact strength in the cryogenic temperature ranges. (-453°F.)
Thermal Conductivity - Tungsten carbide is in the range of twice that of tool steel and carbon steel.
Electrical Conductivity - Tungsten carbide is in the same range as tool steel and carbon steel.
Specified Heat - Tungsten carbide ranges from about 50% to 70% as high as carbon steel.
Weight - The specific gravity of tungsten carbide is from 1-1/2 to 2 times that of carbon steel.
Hot Hardness - When temperature increase to 1400°F, tungsten carbide retains much of its room temperature hardness. At 1400°F, some grades equal the hardness of steels at room temperature.
Tolerances - Many surfaces of even complete parts can be used the way they come from the furnace, "as sintered", such as mining or drilling compacts. In those parts requiring precision ground accuracy, such as stamping dies, close-tolerance preforms are provided for grinding or EDM.
Methods of Fastening - Tungsten carbide can be fastened to other materials by any of three methods; brazing, epoxy cementing, or mechanical means. Tungsten carbide's low thermal expansion rate must be carefully considered when preforms are provided for grinding or EDM.
Coefficient of Friction - Tungsten carbide compositions exhibit low dry coefficient of friction values as compared to steels.-
Galling - Tungsten carbide compositions have exceptional resistance to galling and welding at the surface.
Corrosion-Wear Resistance - Specific grades are available with corrosion resistance approaching that of noble metals. Conventional grades have sufficient resistance to corrosion-wear conditions for many applications.
Wear-Resistance - Tungsten carbide wears up to 100 times longer than steel in conditions including abrasion, erosion and galling. Wear resistance of tungsten carbide is better than that of wear-resistance tool steels.
Surface Finishes - Finish of an as-sintered part will be about 50 microinches. Surface, cylindrical, or internal grinding with diamond wheel will produce 18 microinches or better and can produce as low as 4 to 8 microinches. Diamond lapping and honing can produce 2 microinches and with polishing as low as 1/2 microinch.
Dimensional Stability - Tungsten carbide undergoes no phase changes during heating and cooling and retains its stability indefinitely. No heat treating is required.
Benefits
Because of its exceptional properties, tungsten carbide has, in recent years, emerged as the superior alternative to steel for many industrial applications. Tungsten carbide is a ceramic material composed of approximately a 1:1 ratio of tungsten and carbon atoms. For practical applications it is alloyed with >6% of a softer metal, usually cobalt.
Thanks to its wear resistance and hardness (9.8 Moe's scale), tungsten carbide is ideally suited for wear parts, other machine parts and dies which are subject to severe service conditions. such as high temperatures, corrosion and abrasion
The primary attraction of tungsten carbide is its high strength and low ductility at high temperatures. Other important properties include thermal and electrical conductivity.
Because of its longer wear qualities, tungsten carbide tooling translates into significant cost savings for OEMs, including
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