Microstructure, Hardness, Tensile Strength, and Sliding Wear of Hypoeutectic Al–Si Cast Alloys with Small Cr Additions and Fe‐Impurity Content

Herein, the influence of Cr additions on solidification parameters, as-cast microstructures, and mechanical properties Al–Si alloys with Fe-impurity is investigated. Al–Si–Cr 3% 7% Si 0.25% 0.40% are developed. Solidification experiments performed using an instrumented cooling casting apparatus permitting obtainment vertical upward-solidified ingots. The morphological phase structures characterized by optical scanning electron microscopy X-ray diffractometry. Hardness, tensile, dry sliding wear tests conducted to determine properties. addition leads formation α-Al(Si, Fe)Cr interdendritic precipitates, suppressing undesired needle-like β-intermetallic compounds (Al5FeSi). It noted that both higher alloy content rate induce refinement in dendrite arm spacing, improvement hardness ultimate tensile strength when considering identical content. coefficient friction slightly increases increasing coarsening microstructure. Correlations between secondary spacing proposed, which decreases decrease increase hardness.