An Experimental Investigation in Hard Turning of AISI 4140 Steel

Abstract

There is a growing demand for new and special alloys like nickel alloys, chrome- molybdenum alloys due to their special properties like high strength, light weight, and corrosive resistance. The present work is based on the experimental investigation of chrome-molybdenum alloy to study the effect of process parameters like cutting velocity, feed, and depth of cut on the output responses like force, surface roughness, tool wear. A full factorial design with 33 lay out with total 27 numbers of runs were carried out and optimum cutting condition for all three output responses was found out using grey relational analysis method. White layer formed in a hard turned component is mainly influenced by the abrasive wear of the tool. It has immense response on the performance of product so it is necessary to find out the white layer thickness. To investigate the machined surface properties like white layer and micro-hardness, the sliced machined surface was observed under scanning electron microscope (SEM) and micro-hardness tester respectively. It has been found that the as speed increases, the thickness of white layer increases due to increase in flank wear. Finally, a thermo-mechanical 2D model using finite element method available in Deform 2D TM has been prepared to investigate the output responses like force. Further, the model has been validated comparing the results of simulation with the measured results.