A mathematical model to predict material removal rate during electric discharge machining of cryogenically treated titanium alloys

Abstract

Three grades of titanium alloy Ti (grade 2), Ti-6Al-4V (grade 5) and Ti-5Al-2.5Sn (grade 6) were machined using electric discharge machining after deep and shallow cryogenic treatment. The peak current was observed to be the most significant factor followed by electrode material and pulse-on time. Subsequently, a mathematical model for predicting material removal rate of titanium alloys was developed using dimensional analysis based on the significant process parameters affecting material removal rate and the thermal–physical properties of the titanium alloy. The predicted results obtained from the mathematical model were validated by comparing with the experimental results and were found to be in good agreement with each other. Incremental increase in material removal rate was observed after deep cryogenic treatment due to increase in thermal and electrical conductivity of the material. The model showed that the thermal properties of the material such as thermal conductivity, specific heat and boiling point of materials affect the erosion process in electric discharge machining. Microstructure analysis was carried out using scanning electron microscope, energy-dispersive X-ray spectrometer and X-ray diffraction for selected samples. The migration of different elements and formation of compounds on the machined surface was investigated using energy-dispersive X-ray spectrometer and X-ray diffraction analysis.

Research on discharge characteristics of working mediums of electric discharge machining

“…Especially, A number of researches observed that during the EDM process make it a high potential technology for application in the field of surface modification. 3,4 EDM surface modification is one of the non-conventional surface strengthening techniques, which harden materials surfaces by applying high energy density electrical discharge, it will bring substantial economic benefits to the industry. 5,6 The working process can be divided into four stages:…”

Correlation between Microstructural Alteration, Mechanical Properties and Manufacturability after Cryogenic Treatment: A Review

“…Copper, copper–chromium, and copper–tungsten electrodes were used to get a comprehensive insight into the cryogenic treatments impact. Marginal improvement of MRR was observed [139].…”

Efficient dielectric fluid approach in electrodischarge finish machining on the material surface roughness of titanium alloy Ti-621/0.8

“…Parameters that are likely to affect SR and also cause surface changes on the recast layers were identified using a study from the reported results in the literature [1,4,3]. Three repetitions for each surface roughness measurement were conducted.…”

“…Investigate the effects of cooling time due to pulse off time as prime factor, and peak current intensity as a second factor, of fine machining without using other cooling options, like cryogenically treatment before or in time of processing [1] which provided smooth surface appearance, the cold effect is provided only from the speed and direction of dielectric fluid in the gap area. Regardless of pulse on time which is one of the main factors in MRR (Material Remove Rate), the surface roughness quality is based on efficiency of recasting time of layers [3].…”