Effect of Wire Electrical Discharge Machining on the Surface of Ebm-Additive Manufactured Niti Alloys

Abstract

Nickel-titanium (NiTi) shape memory alloys are used in varied engineering products, such as biomedical device and mechatronic actuator applications. The conventional machining technology are utilized in the limited fields due to their effects on the hardness and brittleness of the machined alloys. However, the wire electrical discharge machining (WEDM) technology is one of the most preferred postprocessing tool to obtain a surface with high quality. The electrical current and voltage values with pulse on and pulse off time are the crucial parameters for WEDM. These parameters should be optimized before wire electrical discharge machining process. Electron beam melting (EBM)-based additive manufacturing of the nickel-titanium powders provides obtaining bulk NiTi shape memory alloys using high energy electron beams. In this study, the application of WEDM which is used as a post-processing tool is evaluated for the EBM-based additive manufactured NiTi samples. Additionally, the scanning electron microscopy, elemental analysis and microhardness characteristics results of the wire electrical discharge machined NiTi samples are carefully investigated.