Effects of electromagnetic stirring on the primary/eutectic phase and mechanical properties of Al-14Ce alloy

Aiming at the poor reinforcement caused by coarse Ce-rich phase in Al-14Ce alloys, the effects of electromagnetic stirring on the Ce-rich phase and mechanical properties during alloy solidification were studied by orthogonal analysis and single variable method. The results show that when the stirring frequency is 21 Hz, the stirring current 50 A and the stirring direction a continuous positive turn, the optimal mechanical properties of the alloy are obtained. The tensile strength reaches 184.6 MPa, the yield strength 107.6 MPa and the elongation rate 7.06%. In the range of 10 to 50 A, with the increase of stirring current, the average size of Al₁₁Ce₃ phase decreases first and then increases, and the mechanical properties decreases first and then increases accordingly. Excessive current up to 70 A is easy to cause coarse primary phase and hole defects, thereby deteriorating the performance. In the range of 7 to 21 Hz, with the increase of stirring frequency, the gradual refinement of Al₁₁Ce₃ phase gradually improves the mechanical properties. However, excessive frequency up to 28 Hz will lead to the aggregation and coarsening of the primary phase, thereby reducing the mechanical properties. Continuous positive rotation is conducive to the alloy organization and performance improvement, while alternating stirring will lead to the aggregation and growth of Al₁₁Ce₃ phase in the local area and thus deteriorates the properties.