Shield Machine Tool material which is the hardest
If I remember correctly, it should be chromium carbide material
Carbide blade is the hardest,
The tool structure is divided into cutter body and blade (alloy). The blade is embedded in the conductor, used to cut the soil, so the blade material is very hard, generally mostly hard alloy (I contact are tungsten alloy), knife body material generally use 40 Luo. According to the definition of Japan, alloy E1 grade is the nearest, HRA greater than 90, bending greater than 1200. Materials are similar, but the heat treatment process is different from Japan to do a good piece.
