7A05铝合金自由锻造工艺及锻件力学性能研究

为得到高性能7A05铝合金锻件,对铸造毛坯制备、锻件制备和锻件热处理进行试验研究。采用半连续铸造工艺制备铸造毛坯,铸造温度为705～710℃,冷却水压为0.05 MPa,铸造速度为50 mm/min;采用一次镦粗加一次拔长锻造工艺,终锻温度为330℃,εZ=87.7%;锻件采用固溶加时效热处理,固溶为(480±5)℃×2 h+水淬,时效为80℃×8 h+120℃×24 h。观察锻件的金相组织并测试其力学性能,锻件微观组织为变形纤维组织,横向力学性能Rm=400 MPa,Rp0.2=360 MPa,A=11%,锻件力学性能与板材力学性能相当。

Research on free forging process and mechanical property of 7A05 aluminum alloy

In order to obtain fine property of 7A05 aluminum alloy forging,preparation of cast blank,preparation of forging and heat treatment of forging were experimented and researched.Cast blank was prepared by semi-continuous casting technology with casting temperature of 705-710 ℃,cooling water pressure of 0.05 MPa and casting speed of 50 mm/min.The forging process includes once upsetting and once drawing-out with finish forging temperature of 330 ℃ and εZ of 87.7%.The solution treatment of forging is(480±5) ℃×2 h+water quenching.The artificial aging is 80 ℃×8 h+120 ℃×24 h.We observed microstructure and tested mechanical property of forging.The results show that 7A05 aluminum alloy forging has deformation fabric-structure with enhanced mechanical properties.Transverse direction mechanical properties are Rm=400 MPa,Rp0.2=360 MPa,A=11%,which are similar with that of plate.