锁紧销表面激光熔覆铁基和镍基合金的组织与性能
Microstructure and properties of laser cladding iron-based and nickel-based alloys on surface of locking pin
乔青峰 1姚小春 2张志坚 2魏家麒1
作者信息
- 1. 中车青岛四方机车车辆股份有限公司,山东青岛 266111
- 2. 陕西天元智能再制造股份有限公司,陕西西安 710049
- 折叠
摘要
针对锁紧销A面易腐蚀、B面易磨损问题,通过在35CrMo钢锁紧销A面和B面分别激光熔覆镍基合金和铁基合金制备熔覆层,研究其微观组织、显微硬度、强度、耐腐蚀性和耐磨性.结果表明,熔覆层与基体之间形成良好的冶金结合,铁基合金熔覆层与基体的剪切强度达到573 MPa以上,两种熔覆层显微组织以树枝晶、柱状晶及等轴晶组成.铁基合金熔覆层的显微硬度为480 HV0.5左右,基体的硬度为280 HV0.5,激光熔覆铁基合金显著提高锁紧销B面的硬度,其耐磨性较基体大幅提高,可减小硬度太高划伤钢轨的风险;镍基合金熔覆层显微硬度与基体相近.铁基和镍基合金熔覆层经240 h中性盐雾试验均未发现腐蚀现象.
Abstract
In view of the problem that the side A of locking pin was easy to corrode and the side B was easy to wear in engineering applications,cladding layers of nickel-based alloy and iron-based alloy were prepared by laser cladding on side A and side B of the 35 CrMo steel locking pin respectively,and the microstructure,microhardness,strength,corrosion resistance and wear resistance of the two cladding layers were studied.The results indicate that metallurgical bonding can be achieved between the cladding layers and steel substrate,and the shear strength of the iron-based cladding layer and the substrate can reach above 573 MPa.The microstructure of the two cladding layers is composed of dendrites,columnar and equiaxed grains.The microhardness of the iron-based cladding layer is about 480 HV0.5,and the microhardness of the substrate is 280 HV0.5,so the laser cladding of iron-based alloy significantly increases the hardness of the side B of the lock pin,and its wear resistance is significantly higher than that of the substrate,which can reduce the risk of scratching the rail with too high hardness.The microhardness of the nickel-based alloy cladding layer is similar to that of the substrate.Both the iron-based and nickel-based alloy cladding layers show no corrosion after 240 h neutral salt spray test.
关键词
锁紧销/显微组织/硬度/剪切强度/耐磨性/耐蚀性Key words
locking pin/microstructure/microhardness/shear strength/wear resistance/corrosion resistance引用本文复制引用
出版年
2024
NETL
NSTL
万方数据