Estimation of wire strength based on residual stresses induced during wire electric discharge machining

摘要: Abstract Frequent breakages of wire electrode during electric discharge machining (WEDM) adversely affect the productivity and surface quality finished products. Uncontrolled thermal loads large stresses generated phenomenon reduce strength which eventually leads to rupture. Thermal residual retained in can cause formation microcracks, voids pits increases probability Thus, it is essential predict prevent breakage for better productivity. This paper presents an approach estimate safety index based on that generate by using a finite element method model. A three-dimensional nonlinear transient thermo-mechanical model molybdenum used WEDM has been developed compute temperature induced stresses. The influence velocity incorporated. computational ability verified conducting systematic experiments. experimental values were obtained X-ray diffraction (XRD) technique. produced observed reach beyond yield stress (600 MPa) at certain process conditions, causes reduction wire. was evaluated calculating ratio (X) between maximum value Formation microcracks considered as indicator threshold be unsafe machining.