高强铝合金半固态精密成型技术应用研究

Applicaiton Research on Semi-solid Precision Forming Technology of High Strength Aluminum Alloy

7000系列高强铝合金已在航空、航天等领域得到广泛应用。但这类高强铝合金因合金元素含量高,存在凝固组织粗大且不均匀、合金元素偏析严重、铸件易开裂等问题,难以直接铸造成型。文中开展了7075铝合金环缝式强电磁搅拌流变制浆及半固态精密成型技术的应用研究。研究表明,环缝式强电磁搅拌半固态精密成型技术有效提高了7075铝合金成分均匀性,铸件组织细化,热裂倾向减少明显,合金的成型性能和零件的力学性能大幅提高,可以实现高强铝合金零件的近净成型。

7000 series aluminum alloy with high strength has been widely used in industries such as aerospace,aviation and so on. Due to its high content of alloy elements,the solidification structure is non-uniform and coarse and alloy elements segregation is serious,resulting in being crack when such alloys are cast,so it is considered to be impossible to cast directly. In this study,the application research of the electromagnetic stirring slurry making technology and the semi-solid precision forming technology of 7075 aluminum alloy are performed. Results show that the semi-solid precision forming technology can effectively improve the homogenization of alloy elements,refine the microstructures of die-casting and squeeze casting parts,improve the forming performance of the alloy,greatly reduce the hot cracking tendency and improve the mechanical properties of alloy parts. Therefore,the near-net-shape of the alloy parts can be realized.