摘要
为提高汽轮机低压末级叶片抗水蚀性能,采用超音速火焰喷涂技术在基体材料1Cr12Ni2W1Mo1V不锈钢表面分别制备了Cr3C2-NiCr涂层和WC-10Co-4Cr涂层;研究了这2种涂层的显微组织、结合强度、显微硬度分布和涂层开裂韧性,测试分析了基体和2种涂层的抗水蚀性能。结果表明:Cr3C2-NiCr涂层和WC-10Co-4Cr涂层都与基体材料结合紧密,平均结合强度分别为69.2 MPa和76.4 MPa;涂层组织致密,孔隙率分别为0.50%和0.07%;2种涂层的平均显微硬度较基体有显著提升,分别达到960.6 HV3 N和1 314.0 HV3N;WC-10Co-4Cr涂层的韧性更好,其开裂韧性平均值达到5.08 MPa·m^1/2,而Cr3C2-Ni Cr涂层仅4.11 MPa·m^1/2。总体而言,2种涂层与基体材料相比均具有较好的抗水蚀性能,尤其是WC-10Co-4Cr涂层抗水蚀性能更优。
In order to improve water erosion resistance of low pressure last stage blades of steam turbines,Cr3C2-NiCr coating and WC-10Co-4Cr coating were prepared on the surface of 1Cr12Ni2W1Mo1V stainless steel by supersonic flam spray.The microstructure,bonding strength,micro-hardness and cracking toughness of the two coatings were studied.The water erosion resistance of the base metal and the two coatings was tested and analyzed.Results showed that Cr3C2-NiCr and WC-10Co-4Cr coatings had strong bonding with the base metal,and the average bonding strength were 69.2 MPa and 76.4 MPa,respectively.The coatings had compact structure with porosity of 0.50%and 0.07%,respectively.The average micro-hardness of the two coatings was significantly higher than that of base metal,reaching 960.6 HV3 Nand 1 314.0HV3 N,respectively.The toughness of WC-10Co-4Cr coating was better,with the average cracking toughness of 5.08 MPa·m^1/2,while the average cracking toughness of Cr3C2-Ni Cr coating was only 4.11 MPa·m^1/2.Generally speaking,the two coatings had better water erosion resistance than the matrix materials,and the erosion resistance of WC-10Co-4Cr coating was better than that of Cr3C2-Ni Cr coating.
作者
章友谊
ZHANG You-yi(Sichuan Engineering Technical College,Deyang 618000,China)
出处
《材料保护》
CAS
CSCD
北大核心
2020年第7期100-104,136,共6页
Materials Protection
