... treatment 3)Bimetallic welding PVC Injection molding machine single screw barrel We ,Lucheng screw Machinery Factory, is one of the most professional ... PVC, PP, PE, PA, PC, ABS .etcDepth of Nitrated Layer: 0.5-0.7mmHardness of nitration: 950-1050HvFragility of nitration ... Hardness of Nitrated Cr coating layer: ≥950HvHardness of Bimetallic Layer: HRC55°-72°Thickness of Cr-coating Layer: 0.03-0.08mmDepth ...