| 引用本文: | 马笑晗,贺定勇,秦志恒,王国红,许一,于金满.TiC对亚共晶高铬铸铁堆焊合金组织及磨损性能的影响[J].中国表面工程,2024,37(4):142~150 |
| MA Xiaohan,HE Dingyong,QIN Zhiheng,WANG Guohong,XU Yi,YU Jinman.Effects of TiC on the Microstructure and Wear Resistance of Hypoeutectic Fe-Cr-C Hardfacing Alloy[J].China Surface Engineering,2024,37(4):142~150 |
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| 摘要: |
| 农机触土部件在作业过程中会受到土壤中沙石、杂草、植物的秸秆、根茬及其他有机质物体的磨损和冲击，极易发生失效报废。为解决农机触土部件耐磨性差、使用寿命短等问题，采用药芯焊丝电弧焊的方法在 Q235 钢基体上进行堆焊，制备含 TiC 的亚共晶高铬铸铁堆焊耐磨层。通过金相显微镜、洛氏硬度计、X 射线衍射仪（XRD）、扫描电子显微镜（SEM）、 能谱仪（EDS）、MLS-225 型湿式橡胶轮磨粒磨损试验机和自制叶轮-滚筒冲击磨损试验装置，分析原位合成 TiC 和粉芯中直接添加 TiC 两种方法对亚共晶高铬铸铁堆焊合金微观组织、硬度、抗磨粒磨损性能及抗冲击磨损性能的影响。结果表明：耐磨堆焊合金主要由 γ-Fe、α-Fe、M7C3和 TiC 组成，TiC 的加入细化了组织中的先析出奥氏体，使得堆焊层宏观硬度增加，磨粒磨损后共晶碳化物的开裂和剥落现象减少，冲击磨损表面材料的脱落减少，磨损失重降低。TiC 可以显著提高堆焊合金的抗磨粒磨损性能和抗冲击磨损性能，其中原位合成方式添加 TiC 的堆焊层性能更加优异，可为 TiC 在农机触土部件耐磨涂层中的研究和应用提供参考。 |
| 关键词: 药芯焊丝 亚共晶高铬铸铁 磨粒磨损 冲击磨损 TiC |
| DOI：10.11933/j.issn.1007-9289.20230906001 |
| 分类号:TG455 |
| 基金项目:泰山产业领军人才项目（Tscx202306085） |
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| Effects of TiC on the Microstructure and Wear Resistance of Hypoeutectic Fe-Cr-C Hardfacing Alloy |
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MA Xiaohan1，HE Dingyong1，2，QIN Zhiheng1，WANG Guohong1，XU Yi3，YU Jinman3
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1.College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124 , China ；2.Beijing Engineering Research Center of Eco-materials and LCA, Beijing 100124 , China ；3.Weihai Tianrun Jinyu New Material Technical Co., Ltd., Weihai 264400 , China
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| Abstract: |
| Soil-engaging components of agricultural machinery are susceptible to physical degradation due to the long-term wear from sand, gravel, weeds, and plant stalks. In order to improve their wear resistance and prolong the service life, a hardfacing alloy of hypoeutectic high chromium cast iron containing TiC was made on the Q235 steel substrate via the flux-cored arc welding method. Effects of in-situ precipitation of TiC and direct addition of TiC to the powder core on the wear resistance of hardfacing alloy were studied by the MLS-225 wet rubber wheel wear tester and self-made impeller-roller impact-abrasion testing machine. In addition, after tests, the samples were characterized using optical microscope (OM), Rockwell hardness tester, X-ray diffraction (XRD),scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS). The results showed that the hardfacing alloy of hypoeutectic high chromium cast iron mainly consists of γ-Fe, α-Fe, M7C3, and TiC, TiC can act as the heterogeneous nucleation core for precipitates austenite first in the organization, increasing their nucleation rate and preventing their growth during solidification, resulting in the refinement of the austenite organization. The TiC introduced by in-situ synthesis has a smaller size and a more diffusely homogeneous distribution than that introduced by direct addition to the powder core. In addition, TiC increased the content of eutectic carbides in the organization and improved the hardness of the hardfacing alloy. The wear forms of all three hardfacing alloys after the abrasive wear test are dominated by micro-cutting, and the grooves on the wear surface of the hardfacing alloy without added TiC are wider and deeper, in the hardfacing alloys with added TiC, the diffusely distributed TiC increased the resistance of abrasive particles cutting, made the grooves shallower, reduced the cracking and spalling of eutectic carbides during the wear process, significantly improved the resistance of hardfacing alloys to abrasive wear. The resistance to abrasive wear performance of TiC hardfacing alloy introduced by in-situ synthesis was 5.2 times higher than that of hardfacing alloy without TiC addition. The surfaces of three kinds of hardfacing alloys after the impact-abrasion test have similar characteristics, due to the periodic impact of abrasive particles leading to hardfacing alloys plastic deformation and work-hardening so that their strength and hardness rose, plasticity and toughness declined, with the continued impact of abrasive particles, cracking occurred in the material and the cracks continue to extend within the material causing it to spalled. The hardness of added TiC hardfacing alloys was higher, can more effectively resist the embedding of abrasive particles, and reduce the generation and expansion of cracks due to the abrasive particles impact on the surface of the material generated by the plastic deformation, the resistance to impact-abrasion performance is more excellent. The resistance to impact-abrasion of TiC hardfacing alloy introduced by in-situ synthesis was 1.2 times higher than that of hardfacing alloy without TiC addition. The resistance to abrasive wear and impact-abrasion of the hardfacing alloy with in-situ precipitation of TiC is better than that of the hardfacing alloy with the direct addition of TiC to the powder core. TiC significantly improved the resistance to abrasive wear performance and impact-abrasion performance of the hardfacing alloy, in which the performance of the hardfacing alloy with in-situ precipitation of TiC is more excellent, which can provide a reference for the research and application of TiC in wear-resistant coatings for Soil-engaging components of agricultural machinery. |
| Key words: flux-cored welding wire hypoeutectic high chromium cast iron abrasive wear impact-abrasion TiC |
