| Composite material is at the forefront of material science,while the steel or iron matrix composite reinforced with ceramic is hot area of research today.Because the composite not only possess high hardness,high wear resistance and other characteristics of ceramic materials,but also possess good toughness and good plasticity of metallic materials.It is of both scientific significance and practical value to prepare and research metal composite reinforced with ceramic,and to be used in harsh wear conditions substitute traditional steel wear resistant materials.Based on the industrial grinder roll of Raymond mill and liner of wet ball mill wear condition,this paper carried out in-depth research on the widely and largely used wear-resistant high manganese steel,which aimed at improving the wear resistance of materials.In this paper,by means of metallographic microscope,hardness tester?brinell hardness and microhardness?,three-body abrasive wear tester,impact abrasive wear tester,scanning electron microscopy?SEM?,electron microprobe analysis?EMP?and other instruments and equipment,systematic comparative study was conducted to analysis the interface in the ceramic reinforce high manganese steel composite material,the microstructure,and wear characteristics?wear resistance,abrasion wear morphology and worn work hardening,etc.?of three-body wear and impact wear.This paper settle the problem that low surface wettability between Al2O3 ceramic and high manganese steel,by the method of chemical nickel-plating.By the means of 3 body high stress abrasive wear tests,and worn surface microscopic morphology observation via SEM,the wear resistance of high manganese steel and Al2O3 ceramic reinforce high manganese steel was conducted.Research the worn work hardening of two kinds materials by testing the sub-surface micro-hardness.The research results show that there are not composition transient and obvious cracks in the bonding interface between the Al2O3 ceramic particles and high manganese steel base in the composite material,which shows that there are not metallurgical bonding,and the mechanical joint is tightly.Under the 3 kg or 5 kg load,the wear resistance of Al2O3 ceramic reinforce high manganese steel is superior to that of high manganese steel,and with the wearing time prolonging,the wear resistance of composite material improves continually.When 3 kg load was applied on specimens,and specimens were worn 120mins,the relative wear resistance of composite material is 1.39 times as much as that of high manganese steel.When 5 kg load was applied on specimens,and specimens were worn 120mins,the relative wear resistance of composite material is 1.27 times as much as that of high manganese steel.Thus it can be seen that under lower load,the relative wear resistance of the composite material is better.The research results show that under the same wearing time,the worn work hardening effect of the high manganese steel and Al2O3 ceramic reinforce high manganese steel under 5 kg load is better than that under 3 kg load.After worn work hardening,the maximum hardness of high manganese steel has reached 580 HV.When higher load was applied,the worn work hardening effect of high manganese steel is obviously better than that of the high manganese steel base in composite material,as a result of the protection from ceramic particles in composite material.By the means of impact abrasive wear tests,and worn surface microscopic morphology observation via SEM,the wear resistance of high manganese steel,Al2O3 rods reinforce high manganese steel and Al2O3 powder reinforce high manganese steel was conducted.Research the worn work hardening of three kinds materials by testing the sub-surface micro-hardness.The research results show that there are composition transient and there are not obvious cracks in the bonding interface between the Al2O3 ceramic powder and high manganese steel base in the composite material,which shows that there are likely to a metallurgical bonding,and the mechanical joint is tightly.Under the condition of 2.5 J and 4.5 J impact load,the wear resistance of Al2O3 powder reinforce high manganese steel is superior to that of high manganese steel.Thus it can be seen that under lower load,the relative wear resistance of the Al2O3 powder reinforce high manganese steel is better.When 2.5 J impact load was applied on specimens,and specimens were worn 60mins,the relative wear resistance of Al2O3 powder reinforce high manganese steel is 6.25 times as much as that of high manganese steel,and the relative wear resistance of Al2O3 rods reinforce high manganese steel is 5.26 times as much as that of high manganese steel.When 4.5 J impact load was applied on specimens,and specimens were worn60mins,the relative wear resistance of Al2O3 powder reinforce high manganese steel is 1.06times as much as that of high manganese steel,and the relative wear resistance of Al2O3 rods reinforce high manganese steel is 0.098 times as much as that of high manganese steel.The Al2O3 rods reinforce high manganese steel have not excellent abrasive resistance,as a result of breakage of Al2O3 rods.When 2.5 J low impact load was applied,the worn work hardening effect of worn surface of tested high manganese steel show that the maximum hardness of high manganese steel has reached 493.7 HV,while the worn work hardening effect of worn surface of tested high manganese steel base of Al2O3 powder reinforce high manganese steel has reached482.4 HV.When 4.5 J low impact load was applied,the worn work hardening effect of worn surface of tested high manganese steel show that the maximum hardness of high manganese steel has reached 522 HV,while the worn work hardening effect of worn surface of tested high manganese steel base of Al2O3 powder reinforce high manganese steel has reached 508.2 HV.The research results show that under the same wearing time,the worn work hardening effect of the high manganese steel and Al2O3 ceramic reinforce high manganese steel under 4.5 J impact load is better than that under 2.5 J impact load.When higher load was applied,the worn work hardening effect of high manganese steel is obviously better than that of the high manganese steel base in composite material,as a result of the protection from ceramic powders in composite material. |
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