As-cast Microstructure and Homogenization Treatment of 2A70 Heat-Resistant Aluminum Alloy

作者：Ren Xin^*; Zhang Junli; Wang Zhao; Liu Jian; Zhang Honghui; Wang Xingrui

来源：Rare Metal Materials and Engineering, 2016, 45(12): 3227-3232.

• heat-resistant aluminum alloy
• thermodynamic calculation
• homogenization treatment
• microstructure

The microstructure of cast 2A70 heat-resistant aluminum alloy was analyzed by optical microscopy (OM) and scanning electron microscopy (SEM). Its homogenization treatment was investigated by differential scanning calorimetry (DSC) and X-ray diffraction analysis (XRD). Meanwhile, the solidification path for the Al-2.4Cu-1.5Mg-1.1Fe-1.1Ni alloy was calculated using the Thermo-Calc software. Based on the calculation, the phases precipitated during solidification were analyzed and the transition temperature of the non-equilibrium eutectic phases was also calculated, which provided a theoretical basis for the research on microstructure and homogenization process. According to the calculated results, the alpha-Al, Al2CuMg, Al2Cu, Al9FeNi, Al7Cu4Ni and Al7Cu2Fe phases exist in the 2A70 alloy, which is in accordance with the experimental findings. In addition, the transition temperature for the non-equilibrium eutectic phases can be approximately substituted by the computed data. The reasonable homogenization treatment process for the investigated alloy is 490 degrees C/12 similar to 16 h+520 degrees C/12 h. During the high-temperature and long-time homogenization process, the non-equilibrium eutectic phases are dissolved completely while the Al9FeNi, Al7Cu4Ni and Al7Cu2Fe change little.

• 出版日期2016-12