Study On Wear Properties And Hardening Behaviors Of Hot-rolled Mn13 Wear-resistant Steel

As the core component of the coal mine machines, Jaw plate was harmed by both the impact and erosion of materials, high impact load and cyclic deformation were the main working conditions that caused serious wear. Production efficiency was influenced by replacing hammer crusher frequently. ZGMn13’s casting flaw and martensitic wear-resistant steel’s low toughness reduced the work efficiency. Hot rolling process could solve these problems. The hot-rolled austenitic high manganese wear-resistant steel(Mn13 steel) was the experimental materials in this paper. In ways of sliding wear test, abrasive wear test and impact abrasion wear test to evaluate the wear resistance comprehensively, Scanning electron microscope(SEM), X-ray diffractometer(XRD) and Transmission electron microscopy(TEM) were used to investigate the mechanism of wear and hardening.In sliding wear test, the abrasive resistance of Mn13 steel was better comparing to B-Hard400 and B-Hard500 steels except conditions of top load dry friction and low load in coal powder sliding. In the conditions of dry friction, the main mechanism was ploughing wear and fatigue fracture wear. The wear mechanisms in conditions of quartz sand and coal powder wear the drilling wear and ploughing wear.Adhesive film of coal powder was occurred under top load. In abrasive wear test, the abrasive resistance of Mn13 steel was better under hard abrasive(quartz sand and coal gangue) which reveal that the effect on work hardening of the hard abrasive was larger than the soft abrasive. In the condition of coal powder, the main mechanism was micro cutting along with fatigue fracture wear. In the condition of coal gangue,the main mechanism was micro cutting along with extrusion and fatigue fracture wear.In the condition of quartz sand, the main mechanism was ploughing wear and micro cutting.The abrasive lose of Mn13 steels exhibited “M” shape under 1-8J impact energy in impact abrasive wear experiment. When the impact energy was 2J and 5J, the abrasive lose showed the highest, and showed the minimum under 4J and 7J. The best impact energy was 3.5-4.5J and 6-7J. The abrasive lose increased with the impact times under 2, 4, 5, 7J impact energy. The character of work hardening of Mn13 steels exhibited different mechanism in high and low impact energy. The thickness of harden layer in Mn13 steel could reach 3500μm and even reach 6500μm under middle and high impact energy. The deformation twins structure could appear in the abrasivesubsurface stratum. And the density of twins increase with the impact energy. Cutting,deformation and fatigue flake were the main in impact abrasive of Mn13 steel. With the increase of impact energy, the work hardening effect becomes higher and cutting mark become lease. The hardening mechanism was dislocation with twin and interaction of high density of dislocation and twin in middle and high impact energy experiment. Besides, nanometer convert, the carbide precipitation, deformedε-martensite and α-martensite appeared assisting to harden the surface in high impact energy condition.