Dissimilar Laser Welding of NiTi Alloy with Ferrous and Non-ferrous Material: Optimization of Process Parameters

Abstract

NiTi Shape Memory Alloy (SMA) is extensively utilized in various high-performance engineering industries such as medical devices, aerospace, air-craft structures, micro-electrical and electronic components, and more, owing to its exceptional properties, including shape memory effect (SME), superelasticity, and biocompatibility. Nonetheless, due to its distinct characteristics, achieving a suitable joint of NiTi alloys is a challenging task. Therefore, scientists have been dedicating significant efforts to the joining of this alloy. This current research explores the weldability of NiTi wires with stainless steel wire and copper wire using Laser. The micro-hardness and the tensile strength of the weld joint are acquired according to Taguchi design of experiment so as to identify the significance of the control factors (laser power, scan speed and focal length). Moreover, simultaneous optimization of multi performance characteristics is also attempted using Utility concept. The results from the confirmation runs showed that the predicted optimal machining parameters has im-proved the individual as well as the multiple performance characteristic.