The flux cored wires with different rare earth oxide additions for hardfacing the workpieces of medium-high carbon steel were developed. The microstrucmre of the hardfacing layer was observed using the optical microsc...The flux cored wires with different rare earth oxide additions for hardfacing the workpieces of medium-high carbon steel were developed. The microstrucmre of the hardfacing layer was observed using the optical microscopy. The average dimension of primary austenite grains in hardfacing layer was measured by image analyzer. The primary austenite grain growth activation energy and index were calculated according to Sellars＇s mode and Beck formula, respectively. Moreover, the effect of rare earth oxide on the growth dynamics of primary aus- tenite grain was analyzed, and then discussed with the misfit theory. The experimental results showed that, by adding rare earth oxide, the av- erage dimension of primary austenite grains in hardfacing layer of medium-high carbon steel decreased, and it was the smallest when the ad- dition of rare earth oxide was 5.17 wt.%. Meanwhile, at this rare earth oxide addition, the primary austenite grain growth activating energy in hardfacing layer was the largest, while its index was the smallest. The calculated results indicated that the primary austenite grain could be refined because LaAlO3 as heterogeneous nuclei of γ-Fe was the most effective.展开更多
在Q235A基体上采用药芯焊丝埋弧焊和自保护明弧焊方式,依次堆焊包含"20Cr2Mn12Ni Mo N韧性过渡层+Cr12W3Mn塑性缓冲层+Cr20Ti Mn Si高铬耐磨层"结构的堆焊合金。借助光学显微镜、扫描电镜、X线衍射仪和显微硬度计等研究堆焊...在Q235A基体上采用药芯焊丝埋弧焊和自保护明弧焊方式,依次堆焊包含"20Cr2Mn12Ni Mo N韧性过渡层+Cr12W3Mn塑性缓冲层+Cr20Ti Mn Si高铬耐磨层"结构的堆焊合金。借助光学显微镜、扫描电镜、X线衍射仪和显微硬度计等研究堆焊合金层的界面组织特征及性能。结果表明,增加韧性过渡层和塑性缓冲层形成了梯度硬度结构的堆焊合金层,不仅可减小残余应力,而且抑制母材成分的稀释影响,规避网状碳化物和共晶等脆性组织形成。展开更多
The effect of heating temperature and thermal-cold recycle times on microstructure and hardness of a W-Cr-Mn-Mo-V Ferro-based hardfacing layer was studied.The results show the surfacing layer has good high-temperature...The effect of heating temperature and thermal-cold recycle times on microstructure and hardness of a W-Cr-Mn-Mo-V Ferro-based hardfacing layer was studied.The results show the surfacing layer has good high-temperature stability and ability to resist quench heat and heat softening.After thermal-cold recycle at 560°C??18°C for 120 times,the hardness of the hardfacing layer is HRC 57.5,its microstructure is mainly tempered martensite and a small amount of retained austenite,when thermal-cold recycled at 680°C??18°C for 120 times,the hardness of the hardfacing layer is HRC 44.5,martensite in the hardfacing layer has almost decomposed.展开更多
在Q235A基体上采用药芯焊丝埋弧焊和自保护明弧焊方式依次堆焊了20Cr2Mn12Ni Mo N塑性缓冲层+含外加Ti C颗粒的耐磨层的堆焊合金,并与无缓冲层的堆焊合金进行分析比较。试验结果表明,增加塑性缓冲层一方面可降低耐磨层成分稀释影响,有...在Q235A基体上采用药芯焊丝埋弧焊和自保护明弧焊方式依次堆焊了20Cr2Mn12Ni Mo N塑性缓冲层+含外加Ti C颗粒的耐磨层的堆焊合金,并与无缓冲层的堆焊合金进行分析比较。试验结果表明,增加塑性缓冲层一方面可降低耐磨层成分稀释影响,有利于耐磨合金层组织保持稳定;另一方面有效降低堆焊合金层的硬度梯度,使之避免残余应力集中而导致过早失效。展开更多
基金Program supported by National Nature Science Foundation of China(51271163)Key Project of Science and Technology of Hebei Province(09215106D)
文摘The flux cored wires with different rare earth oxide additions for hardfacing the workpieces of medium-high carbon steel were developed. The microstrucmre of the hardfacing layer was observed using the optical microscopy. The average dimension of primary austenite grains in hardfacing layer was measured by image analyzer. The primary austenite grain growth activation energy and index were calculated according to Sellars＇s mode and Beck formula, respectively. Moreover, the effect of rare earth oxide on the growth dynamics of primary aus- tenite grain was analyzed, and then discussed with the misfit theory. The experimental results showed that, by adding rare earth oxide, the av- erage dimension of primary austenite grains in hardfacing layer of medium-high carbon steel decreased, and it was the smallest when the ad- dition of rare earth oxide was 5.17 wt.%. Meanwhile, at this rare earth oxide addition, the primary austenite grain growth activating energy in hardfacing layer was the largest, while its index was the smallest. The calculated results indicated that the primary austenite grain could be refined because LaAlO3 as heterogeneous nuclei of γ-Fe was the most effective.
文摘在Q235A基体上采用药芯焊丝埋弧焊和自保护明弧焊方式,依次堆焊包含"20Cr2Mn12Ni Mo N韧性过渡层+Cr12W3Mn塑性缓冲层+Cr20Ti Mn Si高铬耐磨层"结构的堆焊合金。借助光学显微镜、扫描电镜、X线衍射仪和显微硬度计等研究堆焊合金层的界面组织特征及性能。结果表明,增加韧性过渡层和塑性缓冲层形成了梯度硬度结构的堆焊合金层,不仅可减小残余应力,而且抑制母材成分的稀释影响,规避网状碳化物和共晶等脆性组织形成。
文摘The effect of heating temperature and thermal-cold recycle times on microstructure and hardness of a W-Cr-Mn-Mo-V Ferro-based hardfacing layer was studied.The results show the surfacing layer has good high-temperature stability and ability to resist quench heat and heat softening.After thermal-cold recycle at 560°C??18°C for 120 times,the hardness of the hardfacing layer is HRC 57.5,its microstructure is mainly tempered martensite and a small amount of retained austenite,when thermal-cold recycled at 680°C??18°C for 120 times,the hardness of the hardfacing layer is HRC 44.5,martensite in the hardfacing layer has almost decomposed.
文摘在Q235A基体上采用药芯焊丝埋弧焊和自保护明弧焊方式依次堆焊了20Cr2Mn12Ni Mo N塑性缓冲层+含外加Ti C颗粒的耐磨层的堆焊合金,并与无缓冲层的堆焊合金进行分析比较。试验结果表明,增加塑性缓冲层一方面可降低耐磨层成分稀释影响,有利于耐磨合金层组织保持稳定;另一方面有效降低堆焊合金层的硬度梯度,使之避免残余应力集中而导致过早失效。
