摘要
电弧熔覆技术是一种成本低且效率高的再制造技术,而高铬铸铁焊丝是常见的耐磨药芯焊丝体系之一。为了探究Mn和B元素对Q345钢板表面高铬铸铁药芯焊丝电弧熔覆再制造层的组织、硬度和耐磨性能的影响,采用光学显微镜、能谱仪、X射线衍射仪、摩擦磨损试验机、超景深显微镜和电子显微镜等对熔覆层的显微组织、元素组成、硬度分布、磨损过程和机理进行了表征分析。结果表明,在电弧熔覆过程中,电解锰和硼铁粉末发生溶解,与熔覆层中元素相互作用形成块状和板条状的初生碳化物及共晶组织。各熔覆层的组织主要有M_(7)C_(3)(M为Fe、Cr和Mn)、M_(3)C、Fe_(23)(C,B)_(6)、马氏体和残余奥氏体等相存在。随着Mn、B含量的增加,熔覆层表面的硬度逐渐上升。增加了质量分数0.70%的Mn元素的熔覆层硬度相对高铬铸铁熔覆层提升10.64%。继续添加质量分数1.20%的B元素,熔覆层表面硬度进一步提升。熔覆层表面耐磨性随着Mn和B含量的增加呈现出先上升后下降的趋势。C、Mn和B的质量分数分别为4.00%、0.80%和0.80%熔覆层的耐磨性能最高,为Q345的23.06倍。
Arc cladding technology is a low-cost and efficient remanufacturing method.High-chromium cast iron welding wire is one of the common wear-resistant flux-cored wire systems.In order to investigate the effects of Mn and B elements on the microstructure,hardness and wear resistance of the high-chromium cast iron flux-cored wire arc cladding remanufacturing layer on surface of Q345 steel plates,the microstructure,elemental composition,hardness distribution,wear process and mechanisms of the cladding layer were characterized and analyzed using optical microscopy,energy-dispersive spectroscopy(EDS),X-ray diffraction(XRD),friction and wear testing machines,super depth-of-field microscopy and electron microscopy.Results showed that during the arc cladding process,electrolytic manganese and ferroboron powders dissolved and interacted with elements in the cladding layer to form blocky and lath-like primary carbides and eutectic structures.The microstructures of the cladding layers mainly consisted of M_(7)C_(3)(M for Fe,Cr and Mn),M_(3)C,Fe_(23)(C,B)_(6),martensite and retained austenite phases.With the increase in Mn and B content,the surface hardness of the cladding layer gradually increased.When the Mn content added 0.07%(mass fraction),the hardness of the cladding layer increased by 10.64%.Further addition of 1.20%(mass fraction)of B element resul-ted in an additional 27.84%increase in surface hardness of the cladding layer.The wear resistance of the cladding layer surface first increased and then decreased with the increase in Mn and B content.The cladding layer with mass fractions of C,Mn and B at 4.00%,0.80%and 0.80%,respectively,exhibited the highest wear resistance,being 23.06 times that of Q345.
作者
徐家国
胡永乐
仝永刚
王开明
华熳煜
牟双全
黄皓天
XU Jiaguo;HU Yongle;TONG Yonggang;WANG Kaiming;HUA Manyu;MOU Shuangquan;HUANG Haotian(School of Automotive and Mechanical Engineering,Changsha University of Science and Technology,Changsha 410114,China)
出处
《材料保护》
CAS
CSCD
2024年第7期199-206,共8页
Materials Protection
基金
湖南省科技创新计划(2021RC3096)
湖南省教育厅科学研究项目(23A0264)。
关键词
电弧熔覆
药芯焊丝
显微组织
硬度
耐磨性
arc cladding
flux-cored wire
microstructure
hardness
wear-resistance
