Experimental investigation and modeling of hot machining operation using high-strength material

Abstract

High strength work materials have tremendous applications in the field of aerospace, nuclear, biomedical, automotive, etc. It is a challenging task to machine these high strength materials. Costly cutting tools are required to machine those materials. Hot machining is another alternative approach for hot machining those hard material using low cost cutting tools. Basic concept behind the hot machining is to soften the material by heating technique which reduces the shear strength of the workpiece as well as reduces the forces required to machine the workpiece at the time of machining. In the present investigation, experimental investigation of hot machining operation has been carried out using flame heating for machining high manganese steel using ordinary carbide insert.

Hot machining operation has been investigated to study the advantages of hot machining operation over conventional machining operation. Tool wear, surface roughness, chip reduction coefficient, tool life and power consumption have been measured as per the design of response surface methodology technique. This technique has been used to determine the optimum conditions for the desired responses (minimum tool wear, minimum surface roughness, minimum chip reduction coefficient, minimum power consumption and maximum tool life). Principal component analysis (PCA) coupled with Grey relational analysis (GRA) and weighted principal component analysis (WPCA) have been used for optimizing the multi-performance characteristics. WPCA has been proved to provide better results as compared to PCA coupled with GRA with the help of confirmatory test. Fuzzy TOPSIS approach has been used for optimizing performance characteristics namely, tool life and power consumption. It has been proved that Fuzzy TOPSIS is an alternative approach for practical based problems using the decisions that have been taken by decision maker based on experience and skill. FEM modelling has been carried out to determine temperature at the chip/tool interface and validated by experimental results.