Cr元素对热轧耐磨钢显微组织和耐磨性的影响

对两种热轧耐磨钢(Cr质量分数分别为0和0.65％)经过在线层流冷却后的组织性能进行了研究,使用磨损试验机MLG-130在60 N载荷下进行摩擦磨损试验,利用场发射扫描电镜分别对试样磨损表面进行观察.两种耐磨钢冷却后组织为铁素体和马奥岛,由于Cr元素的加入,含Cr钢组织中以马奥岛为主,体积分数为82.6％.此外,在不同...

Effect of chromium on microstructure and wear resistance of hot-rolled wear-resistant steel

Microstructures and mechanical properties of two hot-rolled wear-resistant steels with 0 and 0.65% Cr were investigated after online laminar cooling. Wear tests of samples were carried out by MLG-130 abrasion-test equipment under the load of 60 N. Then worn surfaces of samples were studied by field emission scanning electron microscopy (SEM). These results showed that the microstructure of both wear-resistant steels consisted of ferrite and martensite/austenite constituents. Due to Cr addition, the microstructure of Cr-alloyed steel was dominated by martensite/austenite constituents, the volume fraction of which was 82.6%. Moreover, the wear resistance of the Cr-alloyed steel was better than that of the Cr-free steel after wear testing with different times. After wear testing for 0.5, 1 and 1.5 h, the abrasion weight of the Cr-alloyed steel was 0.357 8,0.769 5 and 1.427 2 g and the wear resistance is 0.48, 0.30 and 0.22 g-1, respectively. The worn surface of the Cr-free steel was characterized by furrows and peeling pits, and the main wear mechanism was micro-furrow and micro-fracture. For the Cr-alloyed steel, plastic deformation was suppressed due to its higher yield strength and hardness, which caused the worn surface became smoother and flatter, and the main wear mechanism was micro-cutting and micro-fracture.