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讨论机械球磨Al5083合金和Al5083?5wt.％B4C复合材料在室温和200°C下的摩擦行为和磨损机制.结果表明,由于常温下的氧化磨损,形成可保护试样表面的机械混合层.在室温和80 N载荷下,Al5083和Al5083?5wt.％B4C球磨样品有磨损迹象,但体积磨损量有限,磨损率分别为5.8×10?7和4.4×10?7mm3/(m·N).在200°C和80 N载荷下,球磨Al5083样品磨损严重,磨损率达10.8×10?7 mm3/(m·N);Al5083?5wt.％B4C样品的磨损较轻,局部出现三体磨损,磨损率为5.3×10?7 mm3/(m·N).位错钉扎和Hall?Petch理论等强化机制、高硬度和载荷传递效应是决定Al5083?5wt.％B4C复合材料磨损行为的关键因素.另一方面,球磨Al5083样品在200°C下磨损率较高可能与其局部晶粒长大和硬度下降有关.“,”Tribological behavior and wear mechanisms of mechanically milled Al5083 alloy and Al5083?5wt.％B4C composite at room temperature and 200 °C were discussed. Results revealed that due to the oxidative wear at room temperature, a mechanically mixed layer (MML) was formed to protect the surface of the samples. Under 80 N of load at room temperature, the milled Al5083 and the Al5083?5wt.％B4C samples showed evidence of abrasion with limited volume loss. In this case, the wear rates were 5.8×10?7 and 4.4×10?7 mm3/(m·N), respectively. At 200 °C and under 80 N of applied load, severe wear occurred in the milled Al5083 sample, and wear rate reached 10.8×10?7 mm3/(m·N) while the Al5083?5wt.％B4C sample showed mild wear with local 3-body abrasion and the wear rate reached 5.3×10?7 mm3/(m·N). Strengthening mechanisms such as dislocation pinning and the Hall?Petch theory, high hardness and the load transfer effect were crucial in determining the wear behavior of the Al5083?5wt.％B4C composite. On the other hand, the milled Al5083 sample represented a relatively high wear rate at 200 °C, which seemed to be related to the local grain growth and a drop in its hardness.