流变挤压铸造7075铝合金的组织及力学性能

Research on Mechanical Property and Structure of 7075 Wrought Aluminum Alloy through Rheocasting

以7075铝合金为例,对变形铝合金流变成型的组织和力学性能进行了研究,探讨了采用流变成型方法生产高性能变形铝合金的可行性。试验证明,通过斜坡冷却法直接获得半固态浆料,结合特殊的挤压铸造工艺,获得了组织致密,无微观气孔、微观缩孔的优良工件。通过3个成形比压水平(80MPa,87MPa,95MPa)和3种热处理制度下7075铝合金的组织性能对比,发现流变成形工件的性能远优于同等材质的金属型普通铸造工件,最高抗拉强度达到502MPa,接近于锻件水平,随着比压增大,工件的致密度随之提高,但强度提高不明显。不同热处理对于流变成形7075变形铝合金的抗拉强度影响不明显,但时效作用对于伸长率影响很大。

Some research are carried out on the mechanical property and structure of wrought aluminum alloy through rheocasting using the technique of liquid forging taking the 7075 aluminum alloy as an example,. It mainly discussed the possibility of rheocasting the wrought aluminum alloy. Dense parts without flaws such as micro gas holes and micro shrinkage cavities were produced using cooling-slope to get semi-solid slurry directly and advanced liquid forging technique under three pressure levels(80 MPa,87 MPa,95 M...