Microstructure and mechanical properties at elevated temperature of Mg-Al-Ni alloys prepared through powder metallurgy

• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2017,（9）
• 页码范围: 947-953
• 页数: 7页
• 语种: 英文

摘要

Mg-Al-Ni alloys were prepared by powder metallurgy,and their microstructure and elevated temperature mechanical properties were investigated.Results indicate that,in addition to α-Mg matrix,both coarse Al3Ni2 particles and fine AlNi nano-particles exist in the Mg-Al-Ni alloys.The strength at 150 ℃is improved with the increase in Ni content.Mg-18.3Al-8Ni alloy possesses a compressive strength of 234.7 MPa and a yield strength of 146.5 MPa.Plasticity is also improved with a low concentration of Ni.Mg-11.3Al-2Ni alloy possesses a compression ratio of 17.3％.The phases of Al3Ni2 and AlNi in the alloys block the movements of grain boundaries and dislocations during the deformation at elevated temperature,The existence of AlNi phase provides a non-basal slip system,leading to the improvement in plasticity.Finally,the formation mechanism of Al-Ni phases in the process is discussed with thermodynamics and kinetics.