采用激光熔覆技术对磨损失效的Nimonic 80A气门进行修复。利用金相显微镜观察熔覆层组织，用扫描电镜和能谱仪对熔覆层进行组织和成分分析，研究熔覆层硬度的变化，采用渗透探伤检测熔覆层表面缺陷，对合格的再制造气门进行装机考核实验。结果表明：激光熔覆层组织主要由柱状树枝晶和枝晶间的共晶组织组成，熔覆层和基体之间形成冶金结合，熔覆层内部无气孔和微裂纹等缺陷；熔覆层平均硬度较基体提高了37.7%；再制造气门的耐磨性是新气门的1.5倍。
The worn Nimonic 80A valve was repaired by laser cladding. Metallurgical microscope,SEM,EDS and penetrant inspection test were used to analyze the microstructure and composition of the cladding layer. The microhardness of cladding layer was measured by Vicker hardness tester. Meanwhile,the experiment of trial run was conducted with the qualified remanufactured valve. Results show that the cladding layer consists of columnar dendrite and interdendritic eutectic structure. The bond between the cladding layer and substrate is mainly metallurgical,and there are no internal defects,such as blowholes and microcracks,in the cladding layer. The average microhardness of the cladding layer is 37.7% higher than that of substrate, and the wear resistance is 1.5 times greater than that of the new valve.
参考文献
| [1] | 装甲兵工程学院.徐滨士院士科研文选[M].北京:机械工业出版社,2001:149-185. |
| [2] | 曹永晟.柴油机气门与气门座圈摩擦副磨损机理分析[J].汽车技术,2011(09):34-37. |
| [3] | 向永华,徐滨士,吕耀辉,姜袆,夏丹.发动机排气门等离子熔覆再制造[J].金属热处理,2010(07):66-69. |
| [4] | 刘蓉,陶锡麒,潘邻,夏春怀,曹庆.激光熔覆技术在机车气门上的应用[J].金属热处理,2003(07):65-67. |
| [5] | 孙建强,潘邻,陶锡麒,曹庆,夏春怀.机车气门密封面激光熔覆钴基合金的应用研究[J].材料保护,2003(04):60-61. |
| [6] | 贾崇田,刘庚武.高温耐热合金Nimonic 80A锻造工艺探讨[J].锻压技术,2006(03):16-18. |
| [7] | 戴华,潘春旭.激光熔覆工艺对Co基合金气门密封面覆层组织的影响[J].机械工程材料,2002(06):25-27,39. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%