... hardness 3.high precision 4.good strength 5.excellent toy car gear Nantong Runfeng Powder Metallurgy Co., Ltd. is ... Powder Metallurgy Co., Ltd. is a professional powder metallurgy manufacturer.2.process:mixing--compacting--sintering--resizing--cleaning--vacuum oiling--packing3 ... and many other field.like transmission gear,spur gear,toy car gear,helical gear,sleeve,copper sleeve,sleeve bearing, bushing, ...