等离子喷涂功率对MoSi<sub>2</sub>涂层组织与抗高温氧化性能的影响

等离子喷涂功率对MoSi₂涂层组织与抗高温氧化性能的影响

摘要: 以自蔓延合成的MoSi2粉体为喷涂原料,采用大气等离子喷涂技术,在K403镍基合金表面制备了MoSi2涂层;采用XRD、SEM和EDS等仪器和高温氧化试验考察了喷涂功率对MoSi2涂层组织和抗高温氧化性能的影响.结果表明:涂层中均含有MoSi2相、Mo5Si3相和钼相,随喷涂功率的增大,涂层的相组成由富硅相向富钼相转变;采用30 kW喷涂功率可制备出主相为MoSi2且致密度较高的涂层,可以明显提高基体的抗高温氧化性能.

Abstract: MoSi2 coating on the surface of K403 nickel-base alloy was prepared by air plasma spraying using MoSi2 powders fabricated by self-propagating synthesis as spraying raw materials.The influence of plasma spraying power on microstructure and high temperature oxidation resistance of the MoSi2 coating was studied by XRD,SEM,EDS and high-temperature oxidation test.The results show that the coating was composed of three phases of MoSi2,Mo5Si3 and Mo.Phase composition of the coating was changed from rich-Si phase to rich-Mo phase with the increase of the plasma spraying power.The compact coating with MoSi2 main phase could be prepared by plasma spraying at 30 kW,which could obviously improve the high temperature oxidation resistance of the substrate.