Tailoring Mechanical and Tribological Properties of Al-Si/Al₂O₃ Composites Produced by Powder Metallurgy via In Situ Al₂O₃ Formation and Machine Learning Insights

This work explores the in situ formation of Al2O3 reinforcement in Al-Si-based composites produced via powder metallurgy, with systematic evaluation of processing parameters and property relationships. Thirty-two compositions were fabricated by varying Si content (2-8 wt.%), SiO2 content (0-9 wt.%), and sintering temperatures (610-640 degrees C). Results confirmed successful aluminothermic reduction of SiO2, yielding homogeneously dispersed similar to 1 mu m Al2O3 particles. The composition containing 2 wt.% Si and 6 wt.% SiO2 sintered at 640 degrees C exhibited the highest Brinell hardness (163.2 HB), while maintaining cost-effectiveness through reduced metallic Si usage. Density and porosity analyses revealed that hardness was maximized at similar to 20-22% porosity, highlighting a trade-off between reinforcement generation and pore formation. Wear tests indicated that low wear rates were not always correlated with higher hardness, suggesting additional mechanisms, such as Si-induced solid lubrication, contribute to tribological performance. Random Forest regression with SHAP analysis identified Si content as the most influential factor, followed by SiO2 ratio and sintering temperature, revealing complex interactions among parameters. Overall, the study demonstrates that optimal mechanical and tribological performance can be achieved through balanced parameter control in multi-component reactive systems. Nevertheless, limitations such as the narrow sintering temperature window and constant duration are acknowledged, pointing to future studies on broader processing ranges and varied wear conditions.

Dergi

JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE

Yıl

2026

ISSN

1059-9495

eISSN

1544-1024

DOI

10.1007/s11665-026-13463-4

WoS UID

WOS:001692873100001