Effect of laser solution-treatment on a Ti-based shape memory alloy

Abstract

Ti-based shape memory alloys are usually heat-treated to produce consistent properties for engineering applications. The objective of this study is to investigate the effects of laser heat treatment on the mechanical properties and superelasticity of Ti72Nb15Zr10Al3 alloy. Samples heat-treated with a single-mode fiber laser (1070nm) were compared with a sample conventionally heat-treated in a furnace at 800°C for 1800s. The samples that were laser heat-treated at 50W for 10s and 100W for 1s had similar mechanical properties. The deformation-induced phase transformation behavior was measured by in situ X-ray diffraction. Recrystallization and grain coarsening during laser heating were observed by high-energy X-ray diffraction. Laser heat treatment achieved the same effects as conventional heat treatment in 1/1000 of the time. Thus, laser heat treatment may be a useful method, especially for fine and precision parts.