Technical Information：

Based on vacuum heat treatment, high frequency quenching,nitriding treatment,hard chrome electroplating, and bimetallic alloy spray welding.

Screw barrel process:

Vacuum heat treatment: done from surface till core

Surface roughness: Ra0.4 μm   
linearity of screw: 0.015mm/m

Function: keep hardness from surface till core with torque resistance

Nitriding layer:

Depth of nitriding layer:0.50~0.80mm
Nitrided hardness:950~1100HV

Nitrided brittleness:less than grade one

Nitriding time:160 hours above

Function: high hard-wearing kept

Hard chrome plating:

Hard chrome plating of hardness after nitriding: ≥950HV

Depth of chrome plating layer: 0.03~0.10mm
Function: with strong flowability and resist high corrosion

Bimetallic layer:

Depth of bimetallic layer:≥3mm
Bimetallic hardness:HRC55-72

Function: work under high temperature with resistant high density adhesion and resist high corrosion

Material type:

Usual material: 38CrMoAlA (JIS SACM645),42CrMo(AISI4140),4Cr5MoSiV1(JIS SKD61),DC53(JISG4404)

Cr12MoV(SKD11),9Cr18MoV, 41CrAlMo7 etc.

Bimetallic alloy materials: Ni-based alloy/Deloro alloy,Fe-based alloy,Co-based alloy,

NiCo-based alloy,Tungsten carbide/Wolfram carbide