STUDY ON CAVITATION RESISTANCE AND WEAR PROPERTY OF NiAl-VC LASER ALLOYED LAYER ON TC4

摘要

In order to improve the cavitation resistance andfrictional wear property of titanium alloy steamblade, NiAl-VC powder was used as alloyingmaterial and irradiated by CO_2 laser to formstrengthened layer on TC4 in this paper. Theprocessing parameters were optimized by differentlaser power, scanning speed and NiAl-VC powderproportion. The laser alloyed layer wascharacterized by optical microscope(OM), scanningelectron microscope(SEM), X-ray diffractionanalysis(XRD) and energy-dispersivespectroscopy(EDS). The microhardness of the laseralloyed layer was measured by micro-hardnesstester. The cavitation resistances and frictional wearproperty of the laser alloyed layer and the substratewere also tested respectively. The results show thatthe strengthening phases, such as TiC, Al_2NiTi_3C,NiTi, Ti_2Ni and Ti_3Al form in the laser alloyed layer.The microhardness of laser alloyed layer increases2-3 times, up to HV_(0.1)996, compared with that of thebase material. In addition, the cavitation resistanceand frictional wear property of the laser alloyedlayer enhance more than 2 times.