Experimental analysis of explosive welding of NiTi alloy

The explosive welding technology for unannealed NiTi shape memory alloy is studied by means of the lower limit method and the design of structure of rigid buffering layer.The chemical composition and structure of welding materials are analyzed with optical microscopy,scanning electron microscope and energy disperse spectroscopy.The results show that the explosive welding of unannealed NiTi shape memory alloy is possible by replacing the flexible buffering layer with the rigid buffering layer and using rigid anvil.The explosive welding has little effect on the chemical composition of welding materials,only a few grain refinement in transition region which is 100 μm from the weld joint.The chemical compositions of the weld joint and the base material are basic identical.It has an important significance that keeps the shape memory function of the NiTi alloy.