退火温度对12Cr1MoV钢表面激光熔覆Stellite 6合金组织与性能的影响OA

Stellite 6 alloy coatings were fabricated on 12Cr1MoV steel via laser cladding and subsequently annealed at dif-ferent temperatures to investigate the effects of annealing on their microstructure and properties.The results indicate that the grain size of the clad layer increases with rising annealing temperature.While low-temperature annealing(450℃)had little influence on the phase composition,annealing at 650℃for 2 h promoted the transformation of the metastable FCC γ-Co phase into the stable HCP ε-Co phase,simultaneously improving microstructural homogeneity and the distribution of car-bides(e.g.,Cr7C3,Cr23C6).However,higher annealing temperatures led to coarsening of both the microstructure and carbide precipitates,accompanied by enhanced diffusion of Fe from the substrate into the coating.Consequently,the hardness and wear resistance of the clad layer deteriorated with increasing annealing temperature.The coating annealed at 650℃exhib-ited the best corrosion performance in 3.5 wt.%NaCl solution,reflected by the highest corrosion potential(-0.284 V)and the lowest corrosion current density(9.967×10⁻7 A/cm2).Further increase in annealing temperature significantly degraded the corrosion resistance.