Research of Multi-Stage Cold Deep Drawing Technique of Long Pure Titanium Cups

为防止癫痫发作，采用市售彩色钛板进行多道次冷拉深成形，制成了纯钛长杯。钛板材具有足够的塑性和较高的r值，但由于与模具材料的高反应性，在拉深过程中容易发生卡箍。对有色纯钛板材进行电化学镀膜处理，以获得有效的防卡蚀氧化物表面层。通过使用商用彩色板材，可以避免板材成形厂家对涂布机的投资，并可以控制氧化层的质量。研究了氧化层厚度、模具材料和润滑剂对多道次拉深过程中卡死现象发生的影响。结果表明，有色纯钛板材在多道次拉深过程中具有足够的防卡扎能力。

Long pure titanium cups were formed by multi-stage cold deep drawing using commercial colored titanium sheets for preventing seizure. The titanium sheets have sufficient ductility and high r-value for the deep drawing, whereas the seizure tends to occur during the deep drawing due to high reactivity with die materials. The colored pure titanium sheets were treated by electrochemical coating so as to get oxide surface layer effective for preventing the seizing. By the use of commercial colored sheets, the investment of coating machines can be avoided in sheet metal forming makers and the quality of the oxide layer can be controlled. The effects of the thickness of the oxide layer, die materials and lubricants on the occurrence of seizure in multi-stage deep drawing were examined. It was found that the coloured pure titanium sheets have sufficient ability in preventing the seizure in multi-stage deep drawing processes.