Product Description
Common Materials
At present, China has a material commonly used screw 45 steel, 40Cr, ammoniation steel, 38CrMOAl, high-temperature alloys.
1) 45 steel cheap, processing performance, but poor corrosion resistance wear.
Heat treatment: quenching HB220-270, induction hardening HRC45--48.
Performance
2) 40Cr steel is better than 45, but often coated with chromium to improve their resistance to corrosion and wear. But require a higher layer of chrome coating is too thin easy to wear, thick is easy peeling, flaking but accelerated corrosion, has been rarely used.
Heat treatment: quenching HB220-270, hard chrome plating HRC> 55
3) nitriding steel, 38CrMoAl relatively excellent overall performance, used widely. Usually the nitride layer of 0.4-0.6 mm. But this material ability to resist corrosion of hydrogen chloride is low, and the price is higher.
4) high-temperature alloy material is superior to other materials, the material without coating, injection molding machine is mainly used for raw halogen-free screw, the material is anti-oxidation high corrosion resistance, heat hra55`60.
Quenched HB220-270, nitriding HRC> 65
Titanium carbide coated foreign helpful ways to improve the corrosion resistance of the surface of the screw, but it was reported that its abrasion resistance is not good enough.
Foreign taken a series of measures in improving the screw wear corrosion resistance. One approach is the use of highly wear-resistant alloy steel. As 34CrAlNi ,, 31CrMo12 like. There take the screw surface coating Xaloy alloy method. This Xaloy alloy with high wear and corrosion properties.