Different surface treatments for screw element

There are different surface treatments for screw element.

1. Tungsten cobalt alloy powder. Processed by special hardening technology, suitable for processing a variety of transparent products, precision products and fiber, magnetic powder, bakelite these special high temperature and high corrosive plastics. 

2. Bimetallic screw element adopts tungsten nickel alloy. The density strength is over 10000psi. The alloy layer thickness is 0.8-2.5mm. The surface hardness of screw is about HRC60 °. 

3. Electroplated screw element. Coat a hard suface of chromium, nickel, titanium and other elements after forming. The coating thickness is 0.03-0.06mm and the hardness is about about HRC60 °. 

4. Stainless steel screw element adopts overall hardening and hardening treatment. The overall hardness is about HRC55 °, which is mainly used for transparent plastic products and processing corrosive plastic. 

5. Nitride screw element. Nitride layer thicness is 0.5mm - 0.8mm and the overall hardness is HV980 to 1080 , suitable for processing ordinary plastic. It adopts spraying, welding or casting way to coat high strength and high hardness alloy material (such as WC, tungsten carbide).