加工硬质合金冲头时,需要在两端面配上钢质的工艺加长。我们采用氧乙炔焰钎焊(此种设备价廉,应用广),使用的钎料是国际上通行的专用硬质合金银基钎科,熔点为750℃,虽实行焊前保温缓升温、焊后保温缓降温,但硬质合金内部组织还是受到不同程度的破环,做出的型腔模具寿命极低,原因如下: (1) 热源温度过高 Processing carbide punch, the need to match the two ends of the steel process lengthened. We use oxyacetylene flame brazing (such equipment is cheap, widely used), the use of brazing filler metal is internationally accepted special hard alloy silver brazing Branch, the melting point of 750 ℃, although the implementation of pre-weld insulation slow warming, welding After the slow cooling insulation, but the internal structure of cemented carbide is still subject to varying degrees of broken ring cavity made of very low life, for the following reasons: (1) heat source temperature is too high