高级检索

激光冲击强化对镁合金摩擦磨损性能的影响

Influence of laser shock processing on friction and wear properties of magnesium alloy

  • 摘要: 为了研究激光冲击对镁合金摩擦磨损性能的影响,采用Nd:glass脉冲激光对AM50镁合金表面进行冲击强化处理,对强化区的表面形貌、粗糙度、微观组织、显微硬度、摩擦磨损性能进行了测试与分析。可知激光冲击强化后,试样表面粗糙度略有增加,强化层内含有大量位错与孪晶,强化层显微硬度明显提高,表面的显微硬度值(约67HV)明显高于基体(约40HV),强化层厚约0.8mm。采用球-平面方式进行了干摩擦磨损实验。结果表明,磨损的主要机制为磨粒磨损,激光冲击强化试样的摩擦系数曲线与未处理试样相似,磨损体积略大于未处理试样;激光冲击镁合金的强化效果明显,而对镁合金的摩擦磨损性能影响很小。

     

    Abstract: In order to study the influence of laser shock processing on the friction and wear properties of magnesium alloy, some AM50 specimens were processed with Nd:glass pulse laser, and the surface morphology, roughness, microstructure, micro-hardness and frictional characterization were examined and analyzed. The experimental results showed that, after laser shock processing, the surface roughness was increased slightly, a lot of dislocations and twins were found in the strengthening layer, hardness was improved significantly, surface micro-hardness was improved to about 67HV as compared with about 40HV of the substrate, and the depth of strengthening layer was about 0.8mm. The friction and wear behaviors were investigated using a ball-on-flat apparatus under dry sliding condition. It was found that the main wear mechanism was abrasive wear, the friction coefficient curve of the LSP specimen was similar to that of the untreated specimen, and the wear volume of the LSP specimen was slightly bigger than that of the untreated specimen. Although the effect of laser shock strengthening magnesium alloy is evident, the influence of laser shock processing on the friction and wear properties of magnesium alloy is slight.

     

/

返回文章
返回