Meterial:

Alloy-steel of high-quality

1)38 CrMoALA(JIS SACM645)

2)42CrMo(JIS SCM440)

3)9 Cr18MoV

4)CW6Mo5Cr4V2

5)Quality Duplex Stainlss Steels

6)GH113

7)Quality Powder Metallurgy Raw Materials

Technics

Heat-treatment

Electroplate hard-chrome

ColdThermal Spray Hard Metal Process

Advanced Nitriding Process

Corrosion & Abrasion Resistance Bimetal Spraying Process 

Technical parameter: 
1): Depth of Nitration Layer: 0.45-0.7mm 
2): Hardness of Nitration: 850-1000HV 
3): Fragility of Nitration: Less than grade 2

4): Roughness of the surface: Ra0.4 
5): Straightness of the screw: 0.015mm 
6): Surface Chromium-Plating's Hardness After Nitriding:≥900HB

7): Chromnm-plating Depth:0.05-0.01mm

8): Depth of alloy Layer: 0.8-2mm.