Effect of ECAP process on the Microstructure and Mechanical Properties of Al6061-Gr Composites

In the present study, Aluminium metal matrix composite with Al6061 matrix and Graphite (5-20 mu m) particulate reinforcement of varying composition (2-8wt. %) were prepared by stir casting technique. Significant improvement in tensile strength and ductility was noticed as the weight percent of Gr increases in as cast Al6061-Gr composites. The cast composites have been subjected to annealing treatment at a temperature of 400 degrees C for 4 hours to homogenize the microstructure. The specimens have been prepared from these composites for Equal Channel Angular Pressing (ECAP). The ECAP process was carried out at room temperature using a die with channel angle of 120 degrees and Bc route was adopted for successive passes. The effect of ECAP on the microstructure and mechanical properties of Al6061 - Gr composites were evaluated. After ECAP process, the sizes of the reinforcement particles are not changed but they were distributed uniformly in the matrix. In addition, a significant reduction in the grain size of the matrix alloy was observed. The hardness and tension tests were conducted at room temperature as per ASTM standards. The results are compared with the base Al6061 material and as cast Al6061-Gr composites. There is a significant improvement in the hardness and the Ultimate tensile strength of ECAP processed composites. (C) 2017 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of International Conference on Advanced Materials and Applications (ICAMA 2016).