TiC硬质合金／碳钢爆炸焊接复合板界面微观组织

Investigation on microstructure at the bonding interface of TiC cermet/steel composite plate prepared by explosive welding

用透射电镜、扫描电镜和X射线能谱仪对TiC硬质合金，碳钢爆炸焊接复合板界面微观组织和相组成进行分析。结果表明，界面上有一断续的熔合层，层厚约10μm，层内为尺寸位于几十个一几百个纳米之间的纳米或亚微米超细晶粒，组成相为铁素体、奥氏体和少量TiC。在界面附近碳钢侧可以看到明显的流线状组织特征，铁素体具有板条状马氏体的结构特征，珠光体层片间距减小，呈流线分布。焊接过程中Ti向钢中扩散15μm左右。

Microstructure at the interface of TiC cermet/carbon steel composite plate prepared by explosive welding was analyzed by transmission electron microscopy （TEM）, scanning electron microscopy （SEM） and energy-dispersive spectrometer （EDS）. A discontinuous fusion zone with thickness of about 10ttm is observed at the interface. The grain size of the fusion layer is in the range of several ten nanometer to hundreds of nanometer. The microstructure of the layer mainly consists of austenite and ferrite, and some titanium carbides. A flow layer is observed at the interface near the steel side. The diffusion of Ti into steel about 15μm occurs during explosive welding. The metallurgical bonding is obtained for the TiC cermet/steel composite plate prepared by explosive welding.