通过药芯焊丝的方式制备Fe-Cr-C-Ti-N和Fe-Cr-C堆焊层，讨论堆焊层中TiN对堆焊层耐磨性能和显微组织的影响. 利用洛氏硬度计检测堆焊层的宏观硬度，通过湿砂轮磨损试验机对堆焊层进行磨料磨损试验，利用X射线衍射仪（XRD）、扫描电镜（SEM）、能谱分析仪（EDS）、透射电子显微镜（TEM）等设备进行检测分析. 结果表明，含有TiN的堆焊层中，初生M7C3明显比不含TiN的组织细小，并且堆焊层硬度和耐磨性也相应提高. 通过热力学计算得出，熔池冷却过程中TiN先于M7C3析出. 由动力学计算可知TiN/M7C3的二维错配度为8.43%，TiN可做为初生M7C3的异质形核质点，使M7C3晶粒细化.
Fe-Cr-C-Ti-N and Fe-Cr-C Surfacing layers were prepared by flux cored wires. The effect of TiN on the wear resistance and microstructure of the surfacing layer was discussed. The rockwell hardness tester was used to test the macrohardness of the surfacing layer. The abrasive wear test of the surfacing layer is carried out by the wet grinding wheel wear tester. Using X ray diffractometer (XRD), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM) and other equipment for testing and analysis. The results showed that the primary M7C3 in the surfacing layer containing TiN was significantly smaller than that without TiN and the hardness and wear resistance of the surfacing layer were also improved. Through thermodynamic calculation, TiN is prior to precipitation of M7C3 in molten pool cooling process. According to the dynamics calculations, the two-dimensional misfit of TiN/M7C3 is 8.43%. TiN can be used as a heterogeneous nucleation site for primary M7C3, which refines the M7C3 grains.
[1] 贾华.多元复合强化耐磨堆焊药芯焊丝及堆焊层耐磨机理的研究[D].沈阳:沈阳工业大学, 2018.
[2] 张彦超,崔丽,贺定勇,等. B元素对Fe-Cr-C系耐磨堆焊合金组织和耐磨性的影响[J].焊接学报, 2014, 35(3):89-92 Zhang Yanchao, Cui Li, He Dingyong, et al. Effect of B on microstructure and wear resistance of Fe-Cr-C hardfacing alloy[J]. Transactions of the China Welding Institution, 2014, 35(3):89-92
[3] 刘跃,张国赏,魏世忠.氮合金化耐磨堆焊的研究现状[J].焊接技术, 2012, 41(12):1-4 Liu Yue, Zhang Guoshang, Wei Shizhong. Research of nitride alloy hardfacing[J]. Welding Technology, 2012, 41(12):1-4
[4] 仲崇惠,包晔峰,陈辉.氮元素对不锈钢堆焊层抗腐蚀性能的影响[J].电焊机, 2018, 48(5):101-104 Zhong Chonghui, Bao Yefeng, Cheng Hui. Effect of N element on resistant-corrosion properties of cladding deposited stainless steel[J]. Electric Welding Machine, 2018, 48(5):101-104
[5] Li Q T, Lei Y P, Fu H G, et al. Microstructure and mechanical properties of in situ (Ti, Nb) Cp/Fe-based laser composite coating prepared with different heat inputs[J]. Rare Metals, 2018, 37(10):852-858.
[6] 刘政军,李乐成,苏允海,等.硼对等离子熔覆高硼铁基合金组织和性能的影响[J].焊接学报, 2012, 33(1):45-48 Liu Zhengjun, Li Lecheng, Su Yunhai, et al. Effects of boron on the microstructure and properties of plasma-clad high boron iron base alloy[J]. Transactions of the China Welding Institution, 2012, 33(1):45-48
[7] He Yanan, Song Qiang, Sun Kang, et al. Microstructure and properties of in-situ chromium carbide composite coating by laser cladding[J]. China Welding, 2018, 27(4):10-17.
[8] 何芹,徐强,熊中,等.高碳高铬耐磨堆焊合金组织及性能[J].电焊机, 2016, 46(9):20-23 He Qin, Xu Qiang, Xiong Zhong, et al. Microstructure and properties of high carbon and high chrome wear resistant surfacing alloy[J]. Electric Welding Machine, 2016, 46(9):20-23
[9] 胡汉起.金属凝固原理[M].北京:机械工业出版社, 2000.
[10] Bruce L B. The effect of carbide and nitride additions on the heterogeneous nucleation behavior of liquid iron[J]. Metallurgical Transactions, 1970, 1(7):1987-1995.
[11] 万响亮,李光强,吴开明.原位观察TiN粒子对低合金高强度钢模拟焊接热影响区粗晶区晶粒细化作用[J].北京科技大学学报, 2016, 38(3):371-378 Wan Xiangliang, Li Guangqiang, Wu Kaiming. In-situ observation of grain refinement by TiN particles in the simulated coares-grained heat-affected zong of a high-strength low-alloy steel[J]. Journal of Beijing University of Science and Technology, 2016, 38(3):371-378
[12] Zhang P, Zhou Y, Yang J, et al. Optimization on mechanical properties of Fe7-xCrxC3, carbides by first-principles investigation[J]. Journal of Alloys&Compounds, 2013, 560:49-53.
