This study optimizes key parameters of semi-solid die casting (SSDC) for aluminum alloys to boost cast components’ fatigue performance. SSDC outperforms traditional die casting in reducing porosity and refining microstructures, yet its fatigue properties depend on precise control of interdependent parameters. The research examines how slurry temperature, injection velocity, die temperature and solid fraction affect A356 aluminum alloy’s microstructure, defects and mechanical properties via a comprehensive experiment matrix and relevant tests. Results show a tailored parameter combination forms uniform globular α-Al phase with minimal porosity, raising the 10⁷-cycle fatigue strength by 65% versus conventional die casting. The findings offer an industrial pathway to produce high-integrity aluminum castings with superior durability for fatigue-critical automotive and aerospace applications.

Zhizhi Tang. Optimization of Aluminum Alloy Semi-solid Die Casting Process and Enhancement of Fatigue Performance. Academic Journal of Materials & Chemistry (2026), Vol. 7, Issue 1: 7-12. https://doi.org/10.25236/AJMC.2026.070102.

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