Investigation of Room and High‐Temperature Wear Characteristics of Stir‐Casted LM13/Ilmenite/Boron Carbide Hybrid Aluminum Matrix Composites

Using the stir casting process, hybrid aluminum matrix composites are made by reinforcing LM13 alloy with different amounts (viz., 5, 10, and 15% wt%) and mixing proportions (viz., 1:1, 1:1, and 3:1) of hybrid reinforcement (i.e., ilmenite and boron carbide). Microstructure of LBF (LM13 alloy‐B₄C‐FeTiO₃) composites is basically comprised of spherical silicon and uniformly dispersed reinforced particles. A chemical reaction between the particles, namely ilmenite, and silicon of the base alloy produced strong interfacial bonding, as shown by X‐ray diffraction analysis. Reinforced particles are also responsible for residual strain and reduction in crystalline size which helps in increasing the hardness of LBF composite. In comparison of base alloy, 15LBF‐31 composite shows the highest reduction in grain size, wear rate, and friction coefficient, whereas highest value is obtained for hardness. All samples show a transition temperature of 200 °C, above which the wear rate demonstrates a rapid increase. The improvement in wear properties of LBF composites at high‐temperature conditions is attributed to reduction in stacking fault energy, whereas the increase in stability of oxide layer results in lower friction coefficient value. The wear mechanisms seen in LBF composites are mostly attributed to plowing and adhesion.