钨合金-HR2钢连接界面特性

Research on interface characteristics of tungsten alloy-HR2 steel joint

采用镍作为中间过渡层，通过热等静压（HIP）方法实现了W—Fe—Ni合金与HR2钢的扩散连接．采用拉伸试验测试了连接件的力学性能，采用金相显微镜（OM）、扫描电镜（SEM）、能谱（EDS）分析了连接试样界面的显微形貌及元素扩散行为．结果表明，在1200—1300℃，130MPa，保温保压1h的条件下，可以实现W—Fe—Ni合金与HR2钢的有效连接．拉伸试验中，当载荷达到650MPa时，基体材料发生断裂，连接界面仍保持完好．结果表明，W—Fe-Ni合金与HR2钢结合紧密，连接界面无裂纹存在．母材与过渡层之间发生了充分的互扩散，W，Co，Cr，Mn等元素都扩散到对方母材基体中，镍表现出更易于向W—Fe-Ni合金一侧扩散的特性．连接界面实现了良好的冶金结合．

The W-Fe-Ni alloy was diffusion bonded with HR2 steel using Ni as interlayer by hot isostatic pressing( HIP).The mechanical properties were evaluated by tensile tests. The microstructure of interface and the diffusion behaviors of different elements were analyzed through OM,SEM and EDS. Results show that,effective welding was obtained between W-Fe-Ni alloy and HR2 steel under the condition of 1 200 ~ 1 300 ℃,130 MPa and holding time of 1 hour. The basemetal fractured during the tensile tests when stress raised to about 650 MPa but the interfaces still keep fine. There is no crack between W-Fe-Ni alloy and HR2 steel. Interdiffusion are sufficient through the base metal and interlayer. These elements including W,Co,Cr,Mn diffused to theopposite sides while Ni shows a tendency of diffusing to W-Fe-Ni alloy. The interface presents a good metallurgical binding.