Elevated Temperature Mechanical Properties of in-situ Synthesized TiB2/Al-4.5Cu Matrix Composites

Abstract

Precipitation coarsening characteristics at elevated temperature have a powerful influence on the thermodynamics properties of TiB2 particles reinforced aluminium-copper matrix composites (PRAMCs), aging precipitation of θ-Al2Cu is stable at room temperature, but coarsening occurs at elevated temperature, In this paper, Al-4.5Cu matrix composites with different content TiB2 are prepared via the molten salt reaction to evaluate the microstructures transformation and the related elevated temperature mechanical properties. Experimental results show that yield strength (YS) and ultimate tensile strength (UTS) of TiB2/Al-4.5Cu composites increase with the augment of TiB2 mass fraction, while the elongation decreases gradually both at elevated-temperature of 453k and 493k. The analysis suggests that the remarkable α-Al grain refinement along with pinning effect of TiB2 particles has a great effect on the grain boundary sliding and migration at high temperature. Additionally, interface debonding also affects the damage and fracture of the composites.