Invar钢模具制造工艺研究

复合材料零件固化后型面几乎不再做加工，因此复合材料成型模具的优劣对制品的外形及表面质量起着重要作用。采用GB／T4339～1999标准测试了几种模具材料的热膨胀系数，结果表明Invar钢与复合材料相匹配。通过对Invar钢焊接性能与切削性能进行研究，试验结果表明：采用坡口间隙2mm、堆焊电流170A、保护气体15L／min焊接工艺可得到良好的焊接接头；粗加工采用转速1300～1500r／min、进给速度400mm／min、切深2．5mm，机床运行无异常，刀具未见明显磨损；精加工采用转速2200-2500r／min、进给速度480mm／min、切深0．5mm可得到良好的切削表面。

Manufacturing Technology Research on Invar Steel Mould

Surface of composite parts is no longer processed after curing, so the quality of composite molding is of the important effect to the quality of products＇ shape and surface. Thermal expansion coefficient of several mould material is tested by using the GB/T4339-1999 standard. The results show that Invar steel match with composite material. The welding and milling properties of an Invar steel is studied. The results show that a good welding joint can be obtained by setting the welding line gap of 2 mm, electric current of 170 A, and protecting gas of 15 L/min. It is also seen that the machine operates smoothly and the milling cutter has not been abraded obviously at the rough machining step by setting the rotate speed of 1 300-1 500 r/min, moving speed of 400 mm/min, and milling depth of 2.5 mm. A good milling surface can be obtained at the finish-machining step by setting the rotate speed of 2 200-2 500 r/min, moving speed of 480 mm/min, and milling depth of 0.5 mm.