Abstract:The wear resistance property of quenched 50MnB tempered at 180,200,220 ℃ were studied under different loads on a pinondisk wear tester. The effects of tempering temperatures on wear and friction properties of the sample were analyzed, and the wear mechanism was discussed. The results show the 50MnB sample tempered at 200 ℃ has the best wear resistance, because its microstructure is even more uniform, and the tempering Martensite lathing is tiny. The load has large effect on the wear properties of 50MnB, especially when the load is over 100 N, the friction coefficient is increased, and the adhesive wear and oxidation wear are also increased, which causes the increasing of wear rate greatly. Adhesive wear and oxidation wear are the main wear mechanism during the friction process of 50MnB, along with slight particle wear.