The Investigation Of Wear Behavior Of Ni-based And Ni/ZrO₂ Infiltrated Layer On Cast Steel Substrate

Guide plate is an important accessory device for steel line rolling production which mainly used for induction, gripping roller piece (steel) passed. In the action production the plate wear damage is very serious. Based on the guide plate special working condition. Guide plate material has become really important for innovation and improvement. In this paper a wear-resistant and high temperature oxidation-resistant of the infiltrated Ni based layer and composite layer of ZrO2/Ni were produced on the ZG45 surface through vacuum infiltration technique according to the work condition of guide plate.By using SEM,EPMA,EDS,XRD,microhardnesstester, THT friction tester which made in Switzerland and MM-200 ordinary temperature friction tester the infiltrated phase structure, hardness, ordinary temperature and high temperature wear resistant have been studied. The result showed:The major phase of the Ni based layer were Ni-Cr-Fe,FeB,FeNi and NiB. The microhardness of the Ni based layer is tested. The result showed:The highest hardness of the Ni based layer is 548 HV which happened in the layer subsurface.There is a hardness grades from the Ni based layer to the steel base. The impact ordinary temperature wear resistance of Ni based layer is tested by MM-200 friction tester. The result show:The wear resistant of the Ni based layer is increased obviously comparing with the ZG45 substrate. Wear rate of Ni based surface layer and the substrate differ by one orders of magnitude (The wear rate of ZG45 is 4.99×10-4mm3/m at the loads of 250N.But the wear rate of Ni based layer is 9.6×10-5mm/m at the load of 250N).The wear mechanism was discussed according to the observation results of wear morphologies. The result show: The wear mechanism of layer were mainly controlled by oxidation, transfer, adherence. The high temperature wear resistance of Ni based layer is tested by THT friction tester which made in Switzerland. The result show:The Ni based layer wear rate did not increase according the rise of temperature. The reason is that oxidation film formed under high temperature which changing the wear properties.The major phase of the composite layer of ZrO2/Ni were ZrO2,Cr2B,NiB and FeNi. The impact ordinary temperature wear resistance of ZrO2/Ni layer is tested by MM-200 friction tester. The result show:Wear rate of the surface ZrO2/Ni composite layer and the Ni based infiltrated layer keep in the same magnitude(The wear rate of Ni based layer is 9.6×10-5mm3/m at the load of 250N and the composite layer of ZrO2/Ni is 2.3×10-5mm3/m at the load of 250N).The high temperature wear resistance of ZrO2/Ni layer is tested by THT friction tester which made in Switzerland.The result show: The wear resistance of 15% ZrO2/Ni layer is superior to the wear resistance of 10% ZrO2/Ni layer.The friction coefficient of layer decrease with the temperature rise(The friction coefficient of Ni based layer is 0.78 at the ordinary temperature but the friction coefficient of the layer is 0.35 when the temperature reach up to 450℃).The properties of the material surface would be changed at the high temperature and the friction properties would be changed when Oxygen join in the wear process.By building high temperature wear extent quantify discription mode we know:The wear extent and time were neither linear function relation nor parabola relation. If given the oxidation weight component under the condition of wear the interaction of weightlessness can be estimated.