采用5kW CO2激光设备,在42CrMo基体上制备出原位合成Nb2 (C,N)及V8C7颗粒增强的铁基复合涂层,研究了熔覆层的组织及性能.结果表明:激光熔覆层主要组成相为α-Fe相、γ-Fe相、Nb2 (C,N)及V8C7；增强相颗粒弥散分布在铁基复合涂层中,与母材相比,其磨损失重约为母材的1/8,显著提高了熔覆层的硬度和耐磨性.进一步的抗氧化性实验结果表明,氧化层结构连续致密,与42CrMo基体相比,在750℃/120h恒温氧化后的氧化层的厚度约为基体氧化层厚度的1/8.%Fe-based composite coating reinforced by in-situ synthesized Nb2(C,N) particulates was prepared by 5kW CO2 laser equipment on 42CrMo steel. Microstructure and properties of laser coating were analyzed. The results show that the microstructure of coating consists of α-Fe,γ-Fe phase,Nb2 (C,N) and V8C7. Reinforcing ceramics particulates with granuliferous morphology are uniformly distributed in the Fe-base composite coatings which posses the better oxidation resistance. The wear mass loss of the coating is about one eighth of the 42CrMo substrate. The wear test shows that these reinforcement particulates improve significantly hardness and wear resistance of the coatings. The experimental results of oxidation resistance show that the structure of oxide scale in the coatings is continuous and dense, oxidation scales are about one eighth of the 42CrMo substrate through 750℃ constant temperature oxidation after 120h.
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