Second phase and matrix texture evolution influence mechanical properties of Al-Mg-Al composite plate by HPR with annealing temperature

Abstract

Annealing treatment can determine the quality of heterogeneous composite plate by regulating the matrix and interface structures and interlayer bonding ability. Al-Mg-Al composite plate was used as an example. Al-Mg-Al composite plate was rolled with 50 % reduction by hard plate rolling. After that, it was annealed at 250 ℃, 300 ℃, 350 ℃ and 400 ℃ for one hour respectively. Through microstructure observation and performance test, the results show that the reaction phases of Al3Mg2 and Al12Mg17 were formed at the interface during annealing treatment. As the temperature continued to climb, yield strength and elongation after fracture of Al-Mg-Al composite plate showed a trend of increasing first and then decreasing, in addition, the tensile strength gradually decreased. As temperature reached 300 °C, its performance reached the best, the tear strength increased to 0.367 KN, and yield strength and elongation reached 172 MPa and 14.5 %, respectively. The study showed that although annealing temperature didn't change types of texture configuration of magnesium alloy, it affected the grain growth, resulting in the change of base surface texture and the overall performance of heterogeneous composite plate. This research provides a theoretical basis for precise regulation of microstructure and comprehensive performance of heterogeneous composite plate by annealing treatment.