Study on the Micro structural Properties of Aluminium Alloy Strips Fabricated by the Large Strain Extrusion Machining 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 we reused but none of them have been able to produce complex shapes precisely at low cost. In order to overcome this difficulty 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 property analysis 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 micro hardness have been considered as output parameters. Aluminium alloy AL5052 was used as the raw material. This alloy is widely used in aircrafts, marine, railways and some other important industries. Experiments are carried out in HMT21 lathe with the help of special design 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 morphology of strips were studied using scanning electron microscope (SEM). While measuring the hardness of strips produced it was revealed that hardness of strips was more as compared to the alloy. Similarly, properties of surface were found to be improved.
Keywords - SPD,RSM, SEM, LSEM, Nano Structured Materials