... designs of Bimetallic Twin screw and barrel for plastic extruder machine to meet customer's demand.Product Parameter: Product Bimetallic KMD-50KK Screw Barrel For Plastic MachineHardness after hardening and ... hard chrome coated layer 4Cr5MoSiV1,SKD-61,SKD-11 Sparying bimetal alloy layer and nitriding treatment HPM38,SI36,SUS440,9Cr18MoV High ... /30,25/55,35/75,40/83,45/90-99,48/112-117,50/105-110,51/105- ...