Effects of high magnetic field on the evolutions of constituent phases in 7085 aluminum alloy during homogenization

The evolutions of coarse constituent phases in homogenized 7085 aluminum alloy at different conditions with or without the application of 12 T high magnetic field were examined by using differential scanning calorimetry, scanning electronic microscope, energy dispersive spectroscopy and X-ray diffraction. It is found that the main constituent phases including quaternary phase T(AlZnMgCu), Al7Cu2Fe, and AlTiCuFeSi are present in as-cast 7085 alloy. During homogenization, α + T eutectics become discontinuous and spheroidized, and Al2CuMg phase nucleates and grows along α + T eutectics. High magnetic field significantly accelerates the melting of quaternary phase T and Al2CuMg phase. When the alloy homogenized at 460 °C/10 h + 480 °C/8 h with 12 T magnetic field, the least amount of constituent phases is obtained.