Reviews on the Study of Aluminum Alloys and Aluminum Matrix Composites with High-temperature Anti-creep Behavior

Creep phenomenon is easily generated at high temperatures for aluminum alloys used as structural and conductor materials, which is further deteriorated with an increase of working time. Structural damage of aluminum alloys is even caused by creep, leading to a catastrophic fai-lure. Therefore, efficient improvement in the creep resistance is crucial for aluminum alloys applied in the environments with high temperatures and loads to keep their excellent properties. So far, rare earth treatment, alloying treatment, and adding of reinforcement are the methods to improve the creep resistance of aluminum alloys. The purpose is to refine alloy grains and precipitate high thermal-stability phases that are dispersed in the interior of grains and in grain boundaries. The mechanisms include fine grain strengthening, precipitation hardening, dispersion strengthening, and direct strengthening. These strengthening effects inhibit the glide of dislocations formed in crystal grains and sliding of crystal boundaries, resulting in an evident decrease of steady-state creep rate thereby improving the creep resistance. Others studies have focused on establishing the relatio-nal models between the creep properties and the creep conditions, microstructure and precipitates of aluminum alloys to predict the creep behavior and service life. The models can provide theoretical data which are favorable to the design of aluminum alloys and aluminum matrix composites showing excellent creep resistance at high temperatures. This paper analyzes the creep behavior of aluminum alloys firstly. Focusing on the high-temperature creep mechanisms such as diffusion creep, grain boundary slip, and dislocation creep, the research progresses of anti-creep aluminum alloys and aluminum matrix composites are summarized according to the items of rare earth micro-alloying, multielement micro-alloying, and composite strengthening, etc. The improving mechanisms on high-temperature creep properties are simultaneously revealed. The studies on the establishment of creep theoretical models and prediction of creep life are also reviewed. The challenges and developments of anti-creep aluminum alloys and aluminum matrix composites are finally proposed basing on the above reviews. © 2021, Materials Review Magazine. All right reserved.