Enhancement of Surface Integrity in Turning of Particle Reinforced Aluminium Matrix Composites by Tool Design

Particle reinforced aluminium matrix composites (AMCs) are high-strength lightweight materials consisting of a comparatively soft aluminium alloy and hard embedded ceramic particles. The high hardness of the particles results in excellent abrasion resistance. However, this property lends poor machinability involving high tool wear and surface imperfections on the workpieces. For this reason, CVD diamond tipped indexable inserts were used for turning AA2124 with 25 % volume proportion of SiC particles. The surface integrity is influenced by the tool geometry, which affects the stress condition in the shear zone. In the research described the influence of modified corner geometries and the width of flank wear land were investigated. The results showed that surface roughness values can be decreased by using tools with a wiper geometry. An increasing flank wear land width of the inserts led to a reduction of the surface imperfections. (C) 2012 Published by Elsevier Ltd. Selection and peer-review under responsibility of Prof. E. Brinksmeier