Abstract:In order to enhance the wear resistance of metal surface,NiTiFe alloy coating was prepared on the surface of HT300 substrate by high frequency induction cladding technology.Scanning electron microscope (SEM),energy dispersive spectrometer (EDS),microhardness tester and X-ray diffractometer (XRD) were used to characterize and analyze the microstructure,element composition,hardness,phase composition and bonding with substrate of NiTiFe alloy coating.The friction and wear tester was used to test the tribological properties of the coating and analyze its friction and wear mechanism.The results show that the coating has compact structure,no cracks and gaps,good molding quality,and the average thickness reaches 0.7 mm,which realizes metallurgical bonding with HT300 substrate.The coating mainly consists of three phases,including Fe2Ti,Fe6.94Ti0.36 and Ni3Fe.The addition of Fe element causes lattice distortion and increases hardness of the coating,with an average hardness of 997.36HV,which is about 5 times the average hardness value of the HT300 substrate.Through the friction and wear test,it is found that the friction coefficient between NiTiFe alloy coating and the counter-friction pair is low in the early stage of the test,and it is maintained at about 0.2.The failure of the counter-friction pair leads to the change in the contact form between the friction pairs,resulting in a step in the friction coefficient.With the increase of load,the width of wear marks on the coating is also increasing,and the exposed area of the counter-friction pair is also increasing.After the friction and wear test,the friction surface of NiTiFe alloy coating is smooth and flat,and only slight abrasive wear occurs,the wear volume is much smaller than that of the counter-friction pair.It shows excellent friction and wear resistance.