Microstructural evolution during semisolid state strain induced melt activation process of aluminum 7075 alloy

The effects of compression ratio on the microstructure evolution of semisolid 7075 Al alloy produced by the strain induced melt activation （SIMA） process were investigated. The samples were cold deformed by compression into the different heights up to 40% reduction. The isothermal holding treatments were carried out at 625 ℃ for predetermined time intervals. The results reveal that the average grain size is gradually reduced with the increase of the compression ratio. When the compression ratio surpasses 30%, the above descending trend is not as evident as that below 30% reduction. During the subsequent heat treatments, the recrystallization is induced in the deformed samples by the increasingly accumulated strain energy. The grain growth mechanisms and the microstructural coarsening of the SIMA processed 7075 Al alloy were discussed and confirmed.

金属半固态加工技术的发展及应用

半固态金属加工技术是21世纪前沿性金属加工技术。较详细介绍了半固态金属加工技术的发展过程和半固态加工技术的特点;进一步介绍了半固态加工的主要工艺过程、分析了半固态加工过程的温度变化特点和半固态加工后的铝合金、镁合金及高熔点合金力学性能。最后,介绍了半固态加工技术在制备铝合金零件、镁合金零件、复合材料、梯度材料和金属联结等领域的应用。

铝合金半固态加工技术的应用研究

介绍了北京有色金属研究总院近年来在铝合金半固态坯料制备方面的研究进展以及在半固态触变成形技术工业应用方面的研究开发工作,并就其可能的应用领域及发展状况进行了讨论。同时,介绍课题组在流变成形、合金设计、变形铝合金等方面的研究工作,以促进半固态加工技术在我国工业中的应用。