Stellite-6+VC混合粉末激光熔覆性能的研究

Performance of Clad Layer Using Mixed Powder of Stellite 6 and VC

小功率脉冲激光下飞机叶片的强化是现在急需解决的问题,本试验通过采用光纤传输300 W Nd:YAG脉冲激光熔覆系统,在低碳钢(SM400B)上熔覆Co基合金(Stellite-6)和碳化钒(VC)混合粉末(VC的质量分数变化范围为0~100%),并对熔覆层的性能进行了研究,从而探究小功率脉冲激光下飞机叶片强化的工艺。试验结果表明,随着VC质量分数的增加,熔覆层组织由亚共晶组织转变为过共晶组织。当VC质量分数小于80%时,熔覆层硬度、裂纹敏感性及耐磨性能随VC增加而增加;当VC质量分数大于80%时,由于母材的稀释作用,熔覆层硬度、裂纹敏感性及耐磨性能随VC增加而降低。试验表明,使用Co基合金(Stellite-6)和碳化钒(VC)混合粉末可以形成耐磨性好、硬度高,裂纹敏感性低的熔覆层,对飞机叶片产生较好的强化效果。

The enhancement of the blade of aircraft with small power pulse laser is an urgent problem to be solved.Pulse 300 W Nd： YAG laser facility is used for cladding in this experiment,and Stellite 6 alloy and VC mixed powder are cladded on mild steel（SM400B） plate.Shape of clad layer,microstructure and performance of clad layer are investigated by changing the weight fraction of VC in the range of 0 to 100% to research the process of strengthening the blade of aircraft with small power pulse laser.The experimental results demonstrate that with the increase of the content of VC,the microstructure of the cladding layer is changed from the eutectic structure to the eutectic structure.The hardness,crack sensitivity and wear resistance of the cladding layer are increased with the increase of VC when the content of VC is less than 80%,and when the weight of VC is more than 80%,the hardness,crack sensitivity and wear resistance of the cladding layer decrease with the increase of VC due to dilution effect of parent material.The results show that high quality cladding layer with good wear resistance,high hardness and low crack sensitivity can formed by using Co based alloy（Stellite-6） and vanadium carbide（VC） mixed powder,which can make a great effect in strengthening the blade of aircraft.