Ni含量对高速列车转向架耐候钢焊缝金属微观组织、力学性能及腐蚀行为的影响  

Effect of Ni Content on Microstructure,Mechanical Properties and Corrosion Behavior of Weathering Steel Weld Metal for High-speed Train Bogies

作　　者：王高见[1,2] 刘丽 康丹丹 叶延洪 邓德安[1] WANG Gaojian;LIU Li;KANG Dandan;YE Yanhong;DENG Dean(College of Materials Science and Engineering,Chongqing University,Chongqing 400045;Sichuan Xiye New Materials Co.,Ltd.,Chengdu 611700;Sichuan Railway Vocational College,Chengdu 611732)

机构地区：[1]重庆大学材料科学与工程学院,重庆400045 [2]四川西冶新材料股份有限公司,成都611700 [3]四川铁道职业学院,成都611732

出　　处：《机械工程学报》2024年第18期163-172,共10页Journal of Mechanical Engineering

基　　金：四川省重大科技专项课题资助项目(2019ZDZX0017)。

摘　　要：通过调整合金元素来获得高韧性、高耐候性的高速列车转向架焊缝金属已成为满足高速列车发展的一项挑战。然而,Ni对其影响的研究尚不充分。基于此,研究了高速列车转向架用Ni-Cr-Cu合金体系焊缝金属的镍含量、微观组织、力学性能和腐蚀行为之间的相互关系。光学和扫描电子显微镜研究表明,Ni含量从0.35%增加到0.85%提高针状铁素体比例(约10%增加到14%),M-A组元含量减少(焊态区1.9%减少到0.6%,再热区1.3%减少到0.7%)、焊态区M-A组元尺寸减小,再热区等轴铁素体晶粒细化;焊缝冲击试验结果表明,当Ni含量从0.35%增加到0.85%时,焊缝金属-40℃、-60℃冲击功分别提高45 J、40 J,这得益于焊缝金属铁素体基体韧性的提高、针状铁素体比例的增加、M-A组元的减少及细化、再热区等轴晶的细化等;周期浸润腐蚀试验及电化学试验研究表明,增加Ni含量促进了焊缝金属的内外锈层致密化,提高了焊缝金属耐腐蚀性能。通过研究揭示了Ni含量对焊缝金属组织性能的影响机理及内在联系,为严酷服役环境下高速列车转向架焊缝金属的成分控制提供技术支撑。It has become a challenge for the development of high-speed trains to obtain high toughness and high weather resistance weld metal for bogies by adjusting alloying elements.However,the influence of Ni has not been fully studied.Based on this,the relationship between nickel content,microstructure,mechanical properties and corrosion behavior of weld metal with Ni-Cr-Cu alloy system for high-speed train bogies is studied.The results of optical and scanning electron microscopy show that the increase of Ni content from 0.35%to 0.85%result in the increase of acicular ferrite proportion(about 10%to 14%),the decrease of M-A constituent(1.9%to 0.6%in the welded zone,1.3%to 0.7%in the reheated zone),the decrease of the size for M-A constituent in the welded zone,and the refinement of equiaxed ferrite in the reheated zone.The impact test results indicate that with the rise of Ni content from 0.35%to 0.85%,the impact energy of the weld metal at-40℃and-60℃is improved by 45 J and 40 J respectively,through enhancing the toughness of ferrite matrix,increasing the proportion of AF,reducing the M-A constituent and refining microstructures.Cycle immersion corrosion test and electrochemical test show that the increase of Ni content promote the densification of the inner and outer rust layer,and thus improve the corrosion resistance of the weld metal.The influence mechanism and internal relation of Ni content on the microstructure and properties of weld metal are revealed,which provide technical support for the composition control of weld metal for high-speed train bogies operating in harsh service environment.

关 键 词：高速列车 耐候钢 微观组织 耐腐蚀性 韧性 镍 

分 类 号：TG156[金属学及工艺—热处理]