摘要
The hot deformation behavior and microstructure evolution of 6082 aluminum alloy fabricated through squeeze casting(SC)under different pressures were studied.The alloy was subjected to hot compression tests and 3D hot processing maps were established.The microstructure evolution was studied by optical microscope(OM),scanning electron microscope(SEM),and electron backscattered diffraction(EBSD).It is found that more dynamic recrystallization(DRX)grains are generated during the deformation of the specimen fabricated under higher SC pressure.At high temperature the effect of SC pressure on microstructure evolution weakens due to the dissolution of second phase particles.In addition,uneven second phase particles in specimens fabricated under higher SC pressure compressed with low temperature and middle strain rate would result in flow localization instability.Finally,the optimum deformation conditions for the 6082 aluminum alloy fabricated by SC were obtained at the temperatures of 430−500℃ and the strain rates of 0.01−1 s^(−1).
研究在不同压力下由挤压铸造工艺制备的6082铝合金的热变形行为和显微组织演化。对合金进行热压缩实验并建立3D热加工图。采用光学显微镜、扫描电子显微镜以及背散射电子衍射技术研究合金的显微组织演化。结果表明,在较高挤压铸造压力下得到的试样在热变形过程中产生较多动态再结晶晶粒。在高温下由于第二相颗粒的溶解,挤压铸造压力对热变形后显微组织的影响减弱。此外,当较高挤压铸造压力下制备的样品在低温及中等应变速率下变形时,不均匀第二相分布容易导致流变失稳的发生。最后,得到挤压铸造态6082铝合金的最优加工区域为430~500℃和0.01~1s^(-1)。
基金
financially supported by the National Natural Science Foundation of China (Nos.52090043,51725504)
the Key Research and Development Program of Hubei Province,China (No.2020BAB040)
the Fundamental Research Funds for the Central Universities,China (No.2021GCRC003)。
