Semi-solid microstructure and its evolution of LC9 aluminum alloys prepared with directly heating-isothermal treatment method
来源期刊：中国有色金属学报(英文版)2003年第z1期
论文作者：WANG Wei-wei(王卫卫) SONG Jian-li(宋建丽) HAN Fei(韩 飞)
文章页码：94 - 97
Key words：directly heating-isothermal treatment; aluminum alloys; semi-solid; microstructure evolution
Abstract: Semi-solid microstructure of industrial hot extrusion rod was prepared with directly heating-isothermal treatment method. It is indicated from the results that semi-solid billet with favorable microstructure can be obtained using this method without reheating, and treatment parameters permitted can be varied within a rather wider range. The grain microstructure obtained is better than that obtained with SIMA method. The mechanism is that the original casting grains are diminished greatly after the rod is extruded, and lots of aberrant inner energy is retained in the microstructures, which provides an inner driving force for the subsequent transformation of dendrites to spherical grains under high temperatures. It can be seen from the experimental results that when industrial extrusion rod of LC9 aluminum alloy is heated at 620℃, and held at that temperature for about 25min, perfect fine equiaxial grains can be obtained, and the average grain size is about 80μm.
WANG Wei-wei(王卫卫)1, SONG Jian-li(宋建丽)2, HAN Fei(韩 飞)1
(1. Department of Materials Science and Engineering,
Harbin Institute of Technology (Weihai), Weihai 264209, China;
2. Department of Materials Science and Engineering,
Taiyuan Heavy Machinery Institute, Taiyuan 030024, China)
Abstract:Semi-solid microstructure of industrial hot extrusion rod was prepared with directly heating-isothermal treatment method. It is indicated from the results that semi-solid billet with favorable microstructure can be obtained using this method without reheating, and treatment parameters permitted can be varied within a rather wider range. The grain microstructure obtained is better than that obtained with SIMA method. The mechanism is that the original casting grains are diminished greatly after the rod is extruded, and lots of aberrant inner energy is retained in the microstructures, which provides an inner driving force for the subsequent transformation of dendrites to spherical grains under high temperatures. It can be seen from the experimental results that when industrial extrusion rod of LC9 aluminum alloy is heated at 620℃, and held at that temperature for about 25min, perfect fine equiaxial grains can be obtained, and the average grain size is about 80μm.
Key words:directly heating-isothermal treatment; aluminum alloys; semi-solid; microstructure evolution
