激光表面织构化对45#钢干摩擦特性的影响

Tribological Properties of Laser Textured Surfaces on 45 Steel under Dry Friction

采用LM-YLP-20F-Ⅱ激光打标机对45#钢试件进行表面织构化处理,形成规则排列的直径为500μm左右,深度为120μm左右的圆形微坑阵列。通过环-块线接触摩擦磨损试验,研究面密度分别为0(即无织构)、6.6%、9.1%、13.7%的激光表面织构对干摩擦磨损性能的影响,并采用三维形貌仪和扫描电镜对试件的表面形貌进行分析。结果表明:激光表面织构化对试件表面硬度影响显著,其中无微坑表面的硬度降低,而微坑区域硬度增加;在相同试验条件下,与无织构化相比,织构化试件磨损量明显降低,并且磨损量在一定范围内随着织构面密度的增加而降低;织构面密度对试验稳定后的摩擦因数值影响不大,但织构化使得摩擦因数的波动较无织构时明显。

Surfaces of 45 steel specimens were textured with a LM-YLP-20F-II laser marking machine to produce regu- lar micro-dimples about 500 μm in diameter and 120μm in depth. The tribological properties of the surface textures with the area density of 0 （without surface textures） ,6.6% ,9.1% , 13.7% at dry sliding were studied by ring-block line con- tact friction tests. The morphologies of textures and wear tracks of specimens were observed using a 3 D profiler and a scan- ning electron microscopy. The results show that wear loss of textured specimens is significantly reduced compared with no textured specimens under the same operating condition and the wear loss is decreased with the increase of textures＇ area density within a certain range. The friction coefficient is almost the same whatever the area density of laser surface tex- tures, but the fluctuation of textured surface＇s friction coefficient is more obvious than no textured surface＇s. The effect of laser surface texture on specimen surface hardness is remarkable, and the surface hardness between dimples is reduced, while the hardness of dimple inside and dimple walls are increased.