STUDY OF SURFACE ROUGHNESS & RESIDUAL STRESSES IN CNC TURNING USING TAGUCHI AND GENETIC ALGORITHM

Abstract

To remain competitive, the mechanical manufacturing industries are challenged on a regular basis for having better productivity and good quality products. The required shape, size and finished ferrous and non-ferrous products are conventionally developed by turning the preformed blanks with the aid of cutting tools that have moved in a machine tool past the work piece. Within a real production system, turning process is one of the simple and frequently applied metal removal process among different cutting processes. The surface roughness of the machined components is one of the most important characteristics of quality of product which refers to the variation from the nominal surface. In many applications, surface roughness plays a vital role, such as highly precise fits, fastener holes, artistic requirements and components subject to dynamic loading. Roughness of the surface imposes one of the most major constraint in the choice of cutting parameters and machine tools in process development. A variety of factors such as feed rate, working material properties, hardness, uneven built-up edge, cutting speed, DOC, cutting distance, tool nose radius and cutting edge angles, consistency of the machine tool and configuration of workpiece, chatter, and use of cutting fluids have been found to affect surface finish in turning in varying amounts. Residual stresses have important part to play in machined component performance. Component characteristics affected by residual stress include fatigue life, resistance to corrosion and portion distortion. Residual stresses are improved the functional conduct of machined components. Because of all this, it is required to understand residual stresses conveyed by machining. Research efforts were made up of experimental results, theoretical simulation, simulation of finite elements and different combinations of those efforts. The aims of the current research are as follows: 1. To study the effect of surface roughness and residual stresses on CNC machine by changing the various input factors i.e. CS, FR, DOC. 2. To research the impact of process variables such as CS, FR and DOC on surface roughness and residual stress while CNC turning of the super alloy Inconel718 super alloy.