This study investigated dry sliding wear properties of AZ31 magnesium alloy and B₄C-reinforced AZ31 composites containing 5, 10, and 20 wt.% B₄C with bimodal sizes under different loadings (10–80 N) at various sliding speeds (0.1–1 m/s) via the pin-on-disc configuration. Microhardness evaluations showed that when the distribution of B₄C particles was uniform the hardness of the composites increased by enhancing the reinforcement content. The unreinforced alloy and the composite samples were examined to determine the wear mechanism maps and identify the dominant wear mechanisms in each wear condition and reinforcement content. For this purpose, wear rates and friction coefficients were recorded during the wear tests and worn surfaces were characterized by scanning electron microscopy and energy dispersive X-ray spectrometry analyses. The determined wear mechanisms were abrasion, oxidation, delamination, adhesion, and plastic deformation as a result of thermal softening and melting. The wear evaluations revealed that the composites containing 5 and 10 wt.% B₄C had a significantly higher wear resistance in all the conditions. However, 20 wt.% B₄C/AZ31 composite had a lower resistance at high sliding speeds (0.5–1 m/s) and high loadings (40–80 N) in comparison with the unreinforced alloy. The highest wear resistance was obtained at high sliding speeds and low loadings with the domination of oxidative wear.

本研究调查了 AZ31 镁合金和含 5、10 和 20 wt.% B _{4 C 的 B 4} C 增强 AZ31 复合材料的干滑动磨损性能，该复合材料具有双峰尺寸，在不同载荷（10-80 N）和不同滑动速度（0.1 –1 m/s) 通过销盘配置。显微硬度评估表明，当 B _4的分布C颗粒均匀，复合材料的硬度随着增强体含量的增加而增加。检查未增强合金和复合材料样品以确定磨损机制图，并确定每种磨损条件和增强材料含量下的主要磨损机制。为此，在磨损测试期间记录了磨损率和摩擦系数，并通过扫描电子显微镜和能量色散 X 射线光谱分析对磨损表面进行了表征。确定的磨损机制是磨损、氧化、分层、粘附和热软化和熔化导致的塑性变形。磨损评估表明复合材料含有 5 和 10 wt.% B ₄C 在所有条件下都具有明显更高的耐磨性。然而，与未增强合金相比，20 wt.% B ₄ C/AZ31 复合材料在高滑动速度 (0.5–1 m/s) 和高载荷 (40–80 N) 下具有较低的阻力。最高的耐磨性是在高滑动速度和低载荷下获得的，氧化磨损占主导地位。