Optimization of Tool Wear Rate during Electro Discharge Machining of NiTi Alloys Using Taguchi Method

Abstract:

NiTi alloys are advance materials which possess superior properties such as pseudoelasticity, shape memory effect, high wear resistance, high corrosion resistance and high strength. NiTi alloys causes serious tool wear, hardening of the machined surface and poor surface finish. Electro discharge machining (EDM) is an unconventional machining process which demonstrates high capability to machine NiTi alloys. Present work emphasis on investigating the effect of EDM process parameters on the tool wear rate. Gap current, pulse on time and pulse off time were considered at three levels as input process parameters along with electrical conductivity of workpiece and tool electrode at two levels. Taguchi L₃₆ (2² x 3³) mixed orthogonal array was utilized to design the experimental plan. Based on the statistical analysis at 95% confidence level it was found that tool electrical conductivity, gap current and pulse on time are the most significant factors that influence the tool wear rate. At optimal setting of parameters the predicted value of tool wear rate obtained was 0.00811 mm³/min.

• Periodical: Applied Mechanics and Materials (Volume 787)
• Pages: 260-264
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.787.260
• Online since: August 2015
• Authors: Vijaykumar S. Jatti*, T.P. Singh
• Keywords: Analysis of Variance, Cryogenic Treatment, NiTi Alloys, Taguchi Method, Tool Wear Rate

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