Tool material - tungsten carbide

cemented carbide
Tungsten carbide is made by powder metallurgy process with high hardness and high melting point metal carbides (WC tungsten carbide, TiC titanium carbide, TaC tantalum carbide, NbC niobium carbide, etc.) and binders such as Co, Mo, Ni (nickel).
1. Classification of cemented carbide
According to the different fields of use, the national standard GB/T18376.1-2008 divides cemented carbide into six categories: P, M, K, NS, and H. According to the different wear resistance and toughness of cemented carbide materials used in cutting tools, they are divided into several groups, and 01, 10, 20... and other two digits indicate the group number. If necessary, a supplementary group number can be inserted between the two group numbers, with 05, 15, 25... etc.
1) Class P is an alloy/coating alloy based on TC and WC and Co (Ni+Mo, Ni+Co) as the binder, which is mainly used for the processing of long-chip materials, such as steel, casting, and long-chip malleable cast iron.
2) Class M is an alloy/coating alloy based on WC, with Co as the binder, and a small amount of TC (TaC, NbC), which is mainly used for processing stainless steel, cast steel, manganese steel, malleable cast iron, alloy steel, alloy cast iron and other materials.
3) Class K is an alloy/coated alloy based on WC, with Co as binder, or a small amount of TaC, NbC or CrC, which is mainly used for the processing of short-chip materials, such as cast iron, cold-cast cast iron, short-chipping malleable cast iron, gray cast iron, etc.
4) Class N is an alloy coating alloy based on WC, with Co as the binder, or a small amount of TaC, NbC or Crc, which is mainly used for processing non-ferrous metals and non-metallic materials, such as aluminum, magnesium, plastics, wood, etc.
5) The $ class is an alloy coating alloy based on WC, with C as the binder, or a small amount of TaC, NbC or CrC, mainly processing heat-resistant and high-quality alloy materials, such as heat-resistant steel, various alloy materials containing nickel, cobalt and titanium.
6) Class H is an alloy/coated alloy based on WC, with Co as the binder, and a small amount of Tac, NbC or Cr added, mainly for machining hard cutting materials, such as hard steel, cold cast iron, etc.
2. Characteristics of tungsten carbide tools
Because the carbide content of cemented carbide is much higher than that of high-speed steel, it has the characteristics of high hardness (72~82HRC), high melting point, good chemical stability and good thermal stability, but compared with high-speed steel, its toughness and brittleness are poor, and its impact and bending resistance are low. The hot hardness of cemented carbide is good, and the hardness of cemented carbide tools at 600 °C exceeds that of high-speed steel tools at room temperature, and the cutting efficiency is 5~10 times that of ordinary high-speed steel, which is the main material used in CNC tools at present.