Effect of electromagnetic transport process on the improvement of hydrogen porosity defect in A380 aluminum alloy

The hydrogen solubility in liquid A380 aluminum alloy was determined. When comparing with the conventional No EMT casting condition, hydrogen porosity defect improving amplitudes of 33.8%, 57.9% and 51.2% at casting temperatures 670 °C, 700 °C and 730 °C were observed in A380 ingots casted by the experimental electromagnetic transport (EMT) prototype with plane induction electromagnetic pump (EMP). Negative pressure zone minus normal atmosphere was found in the rectangular pump ditch of the plane induction EMP by electromagnetic-flow coupling analysis. The electromagnetic separation of hydrogen pores preformed in the negative pressure zone decreases the hydrogen solubility before solidification, and the electromagnetic purification of inclusions and the non-entrainment of surface bi-films weaken the heterogeneous nucleation of hydrogen pores during solidification, which result in the improvement of hydrogen porosity defect under the EMT process. Further analysis indicates that the engineering EMT prototype with higher rectangular pump ditch aspect ratio and more negative pressure zone possesses more prominent hydrogen porosity defect improving effect. The EMT process with plane induction EMP is a promising way to transport liquid aluminum alloys during casting with both high casting efficiency and excellent hydrogen porosity defect improving effect.