Transactions of Materials and Heat Treatment

Title：Experimental study on micro-thixomolding in the sheet bulk forming based on micro-convex characteristics

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ClassificationCode：TG379

year,vol(issue):pagenumber：2019,44(4):28-34

Abstract：

Based on the existing research of semi-solid micro-forming, it was attempted to apply in the sheet bulk forming process for the first time, and for the problems of difficult in the forming of micro-convex of 3C products at present, a composite process of micro-thixotropic sheet bulk forming was proposed. Then, the influences of process parameters on the height of forming micro-convex were studied through experiments, and the applicability of process application was discussed. The results show that in the forming process of micro-convex, the order of influencing height factor is: sheet thickness > pressing amount > forming temperature > deformation speed. Furthermore, the sheet thickness has a very important influence on the height of forming convex. With the decreasing of sheet thickness, the forming height of convex increases obviously, which deviates from the rule of sheet bulk forming under the macroscopic solid condition and shows similar scale effect. This phenomenon can be well explained by the friction scale effect of ring upsetting combined with micro-forming. In the process of forming micro-convex, the defects of outer convex hull, convex hull in the top and shrinkage hole in the back are reduced.

Funds：

国家自然科学基金资助项目（51635005）

乔云（1992-），男，硕士研究生 E-mail：cloud_sj@sjtu.edu.cn 通讯作者：于沪平（1963-），男，博士，副教授 E-mail：yuhp@sjtu.edu.cn

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