Dissimilar friction welding of tubular Zr-based bulk metallic glasses

In this study, the similar and dissimilar friction welding of tubular Zr-based BMGs to BMGs and crystalline metals have been tried and compared with the cases of BMG rods.In order to characterize the friction weld interface, the morphology of protrusion formed and the temperature distribution at weld interface during friction welding were measured, and micrographic observation and X-ray diffraction analysis on the weld cross-section were carried out. In the case of friction welding of tubular BMGs, it was possible to suppress the development of protrusion formed at the interior of tube by introducing an insert into the joining part of tube specimen. A successful joining of the bulk metallic glass (BMG) to crystalline metals could be obtained for certain pairs of the material combination through the precise control of friction conditions. The residual strength after friction welding was evaluated by the 4-point bending test and compared with the cases of BMG rods.