Study on rotary impeller refinement of 4004 Al alloy

The effects of gas flow, rotational speed, refining time and still time on rotary impeller refinement of 4004 Al alloy have been studied. The results show that the rotational speed effect of rotary impeller refinement is superior to that of gas flow, refining time and still time. The optimum purification parameters are obtained by orthogonal analysis: rotor speed of 500 r/min, inert gas flow of 0.4 m³/h, refining time of 15 min, and still time of 6 min, and degassing rate can be 68%. Tensile results show that tensile strength and elongation of the alloy are slightly improved with increasing gas flow, rotational speed, and refining time. But the tensile strength and elongation will first increase and then decrease when the tensile strength and elongation are improved to a maximum value.