Application of grey-fuzzy logic for the optimization of process parameters on CNC turning of EN8-steel

International Conference on Applications and Design in Mechanical Engineering 2012 (ICADME 2012) organized by School of Mechatronic Engineering, Universiti Malaysia Perlis (UniMAP), 27th - 28th Februari 2012 at Bayview Beach Resort, Penang, Malaysia.This paper presents an effective approach of greyfuzzy logic to optimize the cutting parameters in CNC turning with respect to multiple roughness characteristics. Four cutting parameters, namely, depth of cut, spindle speed, feed rate and nose radius are optimized considering three surface roughness parameters; centre line average, peak-valley height and maximum height of profile. An orthogonal array (L27), grey relational generation, grey relational coefficient and grey –fuzzy grade obtained from the grey relational analysis which is used as performance index to solve the optimization problem of turning parameters for EN-8 steel. Taguchi orthogonal array, the signal-to-noise ratio, and the analysis of variance are used to investigate the optimal levels of cutting parameters. The confirmation tests are conducted to verify the results and it is observed that grey-fuzzy approach is efficient in determining the optimal cutting parameters based on multiple surface roughness characteristics

Extrusion of Circular Billet through Circular, Triangular and Square Multi-Hole Dies

In extrusion with multi-hole dies, more than one product is produced from the same billet and quite suitable for improving the productivity and to produce small dimensioned products. Many operating parameters like number of holes present on die, hole profile, length of die land, die pockets, extrusion speed and friction condition affect the surface finish, bending and mechanical property of the products get extruded. The equivalent size of products produced by multi-hole extrusion process does not exist in literature. The objective of this research work is to produce the products of equivalent dimension from different profile holes by multi-hole extrusion. In this experimental study, the products of circular, triangular ads square profiles have been produced. The dies of 2-hole, 3-hole and 4 holes have been used. The extrusion load requirement, hardness of the final products and the change in length of parts extruded are investigated. The extrusion with squared holed dies needs more extrusion load than circular and triangular holed dies. The hardness value varies along the extruded product length. The variation in length of the extruded parts is more for the products obtained from dies with squared hole dies.</jats:p