Microstructure and abrasive wear characteristics of in situ vanadium carbide particulate-reinforced iron matrix composites

• In-situ synthesis combining infiltration casting with subsequent heat treatment.
• Heat treatment at 1164 °C for 3 h favors graphite, α-Fe, and V8C7 in the composite.
• The particle size of V8C7 reinforcement was about 2–12 μm.
• The wear resistance increased initially and then decreased with the V8C7 vol %.
• The wear manifested as grooves, broken carbide particles, and re-embedment of debris.

In this work, in situ synthesis with infiltration casting and subsequent heat treatment was applied to fabricate vanadium carbide (V8C7) particulate-reinforced iron matrix composites. The microstructure and wear-resistance of V8C7 particulate-reinforced iron matrix composites with different volume fraction were studied using scanning electron microscopy, X-ray diffraction, and wear testing. The V8C7 particles were uniformly distributed in the matrix, and the size of the V8C7 reinforcement was 2–12 μm. The relative wear resistance of the composites initially increases decreases with higher V8C7 volume fractions. The best wear resistance of the composites was 21.2 times higher than that of gray cast iron under a 20 N load. This was achieved at 24% V8C7 volume fraction. Wear of the composites manifests as grooves, broken carbide particles, and re-embedment of wear debris.