Study on Microstructural Properties of Aluminium Alloy Strips Fabricated By Large Strain Extrusion Machining (LSEM) Process

Abstract

Manufacturing of bulk nano structured are in high demand in today’s industry because of recent development and application of advanced materials. Many traditional machining processes were used but none of them have been able to produce complex shapes precisely at low cost. In order to improve the mechanical and micro structural properties, Large strain extrusion machining (LSEM) is introduced. It is basically a fabrication process. It is a single step manufacturing process. It is a method of severe plastic deformation (SPD) which is used particularly for machining bulk nano structured materials. It is a low cost manufacturing technique with advantage of machining and controlling dimensions simultaneously. Different controlled dimension shapes such as foils, sheets and bars are produced with controlled geometric parameters of the deformation using this machining process. In the present work, experimental investigation and analysis of formed specimen is carried out. Response surface methodology (RSM) has been used to develop the input output relations. Feed, rake angle and speed have been considered as input parameters while shear strain, hardness and surface roughness have been considered as output parameters. Aluminuim alloy AL5052 was used as the ingot material. This alloy is widely used in aircrafts, marine, railways and some other important industries. Experiments are carried out in HMT20 lathe using fabricated tool post. Based on experiments carried out, Box-Behnken design technique has been used to develop nonlinear models. The mechanical properties of the strips produced were measured by micro hardness tester. Also, the surface roughness and surface morphology of strips were studied using surface roughness tester and scanning electron microscope (SEM).