Al–Mg系合金の固液共存域を含む高温域での機械的性質と凝固割れ

抄録

The hot tearing (crack) often occur on the surface of the Al–Mg system alloy ingot during casting process. To explain the mechanism of crack generation in the Al–Mg system alloy, the mechanical properties and deformation behaviors of semi solid state was investigated by the tensile test in the semi solid state. The tensile strength and the elongation of Al–Mg system alloy decrease with increase the test temperature in the solid state to semi solid state. Other system aluminum alloys, for example Al–Si–Fe system alloy and Al–Zn–Mg–Cu system alloy, have large elongation in the solid state near the solidus. Because of low ductility in the temperature range near the solidus, the hot tearing often occur on the surface of the Al–Mg system ingot, in which the casting mold contacts at the solidification.