Preparation of Al₃Ti-Al₂O₃/Al Inoculant and Its Inoculation Effect on Al-Cu-Mn Alloy

The grain size plays a pivotal role in determining the properties of the alloy. The grain size can be significantly decreased by adding inoculants. Aiming to address the shortcomings of existing inoculants, the Al₃Ti-Al₂O₃/Al inoculant was successfully prepared using Al-Ti master alloy and Al₂O₃ whiskers as raw materials. With the aid of ultrasonic energy, the Al₂O₃ whiskers were uniformly dispersed within the inoculants. Under the combined action of ultrasonic and titanium, the Al₂O₃ whiskers were broken into small particles at high temperature. To enhance the morphology of Al₃Ti and achieve even particle dispersion throughout the matrix, vacuum rapid quenching treatment was applied to the inoculant. The SEM test results indicated a significant reduction in particle size after vacuum rapid quenching. The Al₃Ti-Al₂O₃/Al inoculants exhibited excellent grain refinement effects on the weldable Al-Cu-Mn alloy. Crystallographic calculations and HRTEM analysis revealed that Al₂O₃ and Al have orientation relationships, indicating their potential as effective heterogeneous nucleation sites. The mechanical properties of the Al-Cu-Mn alloy were obviously improved after the Al₃Ti-Al₂O₃/Al inoculant was added.