High temperature mechanical behavior of AZ61 magnesium alloy reinforced with graphene nanoplatelets

In present work, graphene nanoplatelets reinforced AZ61 magnesium alloy was synthesized by disintegrated melt deposition method. The synthesized materials were subjected to homogenization at 430 degrees C for 24 hand extruded at 350 degrees C with the ratio of 52:1. Experimental results revealed that graphene nanoplatelets addition have significant effect on refining grain size and changing in basal textures due to their uniform distribution throughout the composite matrix, which results in significant improvement in room temperature micro hardness, tensile and compression strengths. In addition, tensile strength of as extruded graphene nanoplatelets-AZ61 composite was investigated at temperatures ranging from 75 degrees C to 225 degrees C with initial strain rate of 2 x 10(-3) s(-1). The results show that total fracture strain increases and tensile yield strength decreases with increasing testing temperature. The increased fracture strain at high temperature is mainly attributed to significant grain refinement and uniform particle distribution. The fracture surface analysis revealed that deformation possibly occurs through grain boundary sliding accommodated by diffusional transport. (C) 2015 Elsevier Ltd. All rights reserved.