焊管2025，Vol.48Issue(8)：65-72,8.DOI:10.19291/j.cnki.1001-3938.2025.08.008
稀土元素和热处理对高速激光熔覆再制造车轴组织及性能的影响
Influence of Rare Earth Elements and Heat Treatment on Microstructure and Properties of High-speed Laser Cladding Remanufactured Axles
摘要
Abstract
High-speed laser cladding process with co-axial powder feeding was adopted to prepare GH3625-based composite cladding layers with different contents of rare earth oxide CeO₂ on EA4T substrates.Effects of cladding process parameters,CeO₂content,and heat treatment on properties of cladding layers and substrates were studied.Results show that composite powder prepared by current powder mixing method cannot meet powder feeding requirements of laser cladding.Height,width,and heat-affected zone depth of the single-track cladding layer gradually decrease with increase of cladding speed,but dilution zone depth(cladding depth)and dilution rate first increase and then decrease,showing an obvious non-linear relationship.Tensile and yield strengths of GH3625 cladding layer gradually increase,elongation slightly decreases with increase of cladding speed,and the impact energy first increases and then decreases,reaching the highest value at a speed of 0.07 m/s.With increase of CeO₂content,the tensile strength,elongation,and impact energy of GH3625+CeO₂ composite powder first increase and then decrease,showing better comprehensive properties at 0.5%.The highest hardness appears near interface between heat-affected zone and dilution zone,about 340HV0.2～360HV0.2,and gradually decreases with the increase of the distance from the interface due to the reduction of martensite content.The microhardness of cladding layers with different passes is basically equivalent,and the deposition of subsequent passes has a significant effect on the microhardness of the first pass.Due to the self-tempering effect,starting from the third layer,the width of the high-hardness region narrows significantly.The microhardness of the cladding layer changes little before and after different layers and heat treatment.Heat treatment at 500 ℃ and below has little effect on microhardness but significantly improves the strength,plasticity,and toughness of the cladding layer.关键词
高速激光熔覆/GH3625/CeO2/熔覆速度/熔覆层显微硬度Key words
high-speed laser cladding/GH3625/CeO₂/cladding speed/cladding layer microhardness分类
矿业与冶金引用本文复制引用
韩晓辉,霍会宾..稀土元素和热处理对高速激光熔覆再制造车轴组织及性能的影响[J].焊管,2025,48(8):65-72,8.基金项目
中车重大科研项目"基于激光熔覆的列车车轴再制造及质量评价技术研究"(项目编号2023CTA016). （项目编号2023CTA016）
