Session: 03-02-03: Applied Innovations in Solid-State Processes and Surface Engineering: Technologies for Advanced and Sustainable Manufacturing III

Paper Number: 166352

Micro-Wire-EDM Machinability and Surface Study of the New Generation TNZT (Ti-35Nb-7Zr-5Ta) Alloy 

In the previous decade, material scientists have reported on a new generation of titanium alloys which includes zirconium, niobium, tantalum, iron, and molybdenum. Previously, titanium grade 5 (Ti-6Al-4V) was considered the best biomedical, automotive, and aerospace alloy. However, researchers identified Aluminum and Vanadium toxicity in Ti-6Al-4V; moreover, it possesses a higher Young’s modulus than TNTZ alloys. Even though TNTZ alloys offer lower modulus and good corrosion properties, the micromachining of these alloys with conventional methods remains a significant challenge. This study presents an experimental analysis of the micro-wire-electro-discharge machining (µ-WEDM) machinability of the difficult-to-machine new generation Ti-35Nb-13Ta-4.6Zr alloy with tungsten wire of 50µm diameter. µ-WEDM is a machining process that erodes the material from a workpiece, being electrically conductive, irrespective of its hardness. The study hypothesized that the machining performance and the quality of micro-features would differ due to the considerable variation in the thermal and electrical properties of the workpiece and wire materials. To evaluate machinability, machined surfaces of 3mm*20mm, as well as micro-slots 50µm*20mm, were machined on TNTZ alloy specimens. The quality of the micro-features was assessed based on crater area (CR), surface finish (SR), microhardness (MH), kerf width (KF), and volumetric material removal rate (VMRR). The machining conditions were taken as capacitance (1nF, 10nF, & 100nF), and voltage (80, 105, & 130V), each experiment was repeated three times and averaged in order to avoid noise. Later part of the study includes the grey relational grade analysis to identify the optimal parameters. The findings revealed that the micro-features on Ti-35Nb-13Ta-4.6Zr were slightly inferior at higher machining conditions, primarily due to significantly higher capacitance leading to larger spark width, increasing the size of the crater formation and surface hardness. In contrast, smoother surface finishes were achieved at lower machining conditions. At lower machining conditions the VMRR, KF, MH, CR, and SR were recoded as 181366.9 µm³/s, 93.3 µm, 310 HV, 18.9 µm², and 0.5 µm, respectively. Similarly, the rougher surface finish was observed at higher capacitance, VMRR, kerf width, MH, CR, and SR of 481466.9 µm³/s, 127.53 µm, 422 HV, 889.4 µm², and 2.09 µm, respectively. Taguchi predicted capacitance to be the most effective parameter with 92% of contribution, followed by the voltage. Moreover, the optimal parameters were figured out by using grey relation grade (GRG) analysis post experimentation, the GRG analysis suggested that the lower capacitance (1nF) and voltage (80V) to be the optimal input parameters and higher capacitance and higher voltage to be least optimal.

Presenting Author: Asma Perveen Nazarbayev University, Kazakhstan

Presenting Author Biography: Dr. Asma Perveen is an Associate Professor in Mechanical & Aerospace Engineering department at Nazarbayev University (NU), Kazakhstan. Dr. Perveen earned her PhD from National University of Singapore (NUS) under Mechanical Engineering Department in 2012. After completion of her PhD, she worked as Research Scientist at Singapore Institute of Manufacturing Technology (SIMTech) for more than two years. She also worked as Visiting Research Scholar in University of Parma, Italy and Western Kentucky University, USA. Her research interests are on the areas of EDM, hybrid Machining processes, Additive Manufacturing, Polymer extrusion and non-conventional machining processes. She has served as technical committee member, Co-Convener, Convener, session chair for several conferences. She is currently serving as Reviewer and Editorial board member for several reputed journals.

Authors:

Shahid Ali Nazarbayev University
Didier Talamona Nazarbayev University
Asma Perveen Nazarbayev University, Kazakhstan