Application of reaction nitrogen arc cladding TiCN/Fe composite coating on cutter of agricultural machinery

摘要

In order to solve the high-price and short-lifetime problems of the cutter of agricultural machinery,and improve the wear resistance of the cutter,the TiCN/Fe metal ceramic composite coating was prepared on the substrate of Q235 steel by reaction nitrogen arc cladding technique.The mixture powder of titanium and graphite was preplaced on the Q235 steel surface after intensive mixing by planetary ball mill and gluing with starch binder.The microstructure and phase of the coatings,interface behavior between coatings and the substrate were investigated by scanning electronic microscope and X-ray diffractometer.The micro-hardness distribution of the coating section was tested by micro-hardness tester.Friction coefficient and wear weight loss were measured by abrasion machine.Wearing surface morphology was investigated by scanning electronic microscope.The results show that an excellent bonding between the coatings and the Q235 steel substrate is ensured by the strong metallurgical interface and phase of the coatings.The coatings are mainly composed of TiCN.The highest microhardness of the coatings reaches 1 089 HVO.2,while the micro-hardness of Q235 steel substrate is only about 286 HVO.2.The anti-abrasive test results show that the wear resistance of the cladding coating is better than that of quenched and tempered65 Mn steel which is often used as cutter of agricultural machinery.The field test results show that the TiCN/Fe metal ceramic composite coating prepared by reaction nitrogen arc cladding is feasible to the manufacture and remanufacture of the cutter of agricultural machinery.