Technical Information: Material: 38CrMoAlA(JIS SACM645), 42CrMo Bimetal material: Fe based alloy powder, Nickel based alloy powder, Tungsten carbide Technics: 1) Heat treatment 2) Nitriding treatment 3) Centrifugal casting Technical parameter: Nitrided layer depth: 0.7mm Bimetallic layer depth: 3mm Surface hardness: 950HV Nitrided brittleness: Less than grade 1 Surface roughness: Ra0.4 Linearity of screw: 0.015mm. Wooden case.