What are hard alloys? Which ones are they? How often are they chosen?
It is based on one or several carbides (TiC and WC) as the hardening phase, with carbon steel or alloy steel (such as high-speed steel, chrome molybdenum steel) powder as binder, powder metallurgy materials through proportioning, mixing, pressing and sintering. After annealing, it can be machined. After quenching and tempering, it has the same hardness and high wear resistance as the hard alloy. It can also be forged and welded, and has the characteristics of heat resistance, corrosion resistance and oxidation resistance. The utility model is suitable for manufacturing various tools with complicated shapes, such as twist drills, milling cutters, etc., and can also manufacture moulds and wear-resistant parts which work at higher temperature.
Cemented carbide is a hard particle of refractory metals (tungsten, tantalum, titanium, molybdenum, etc.) that is mixed with one or more iron elements (cobalt, nickel, or iron), pressed and molded, and then sintered. Types and properties of cemented carbides: (1) classification and grade of cemented carbides. Tungsten carbide cobalt carbide is mainly composed of tungsten carbide (WC) and binder cobalt (Co). The brand is from "YG" ("hard cobalt" Pinyin prefix) composition and percentage of average amount of cobalt. For example, YG8 is a tungsten cobalt carbide that represents an average WCo = 8% and the remainder is tungsten carbide. Tungsten carbide cobalt carbide is mainly composed of tungsten carbide, titanium carbide (TiC) and cobalt. The grade by "YT" ("hard ti" Pinyin prefix) and the average content of titanium carbide. For example, YT15 represents an average WTi = 15%, while the others are tungsten titanium cobalt carbide with tungsten carbide and cobalt content. The tungsten titanium tantalum (NB) hard alloy is the main component of tungsten carbide, titanium carbide, tantalum carbide (or niobium carbide) and cobalt. This kind of hard alloy is also called universal cemented carbide or universal hard alloy.
