不同后处理对AlCrN涂层结构和性能的影响

电弧离子镀制备的Al Cr N涂层表面存在大量的"大颗粒",导致其具有较高的表面粗糙度,进而降低了涂层的摩擦磨损和切削性能。采用不同后处理方法(如离子刻蚀、湿喷砂、干喷砂和微粒子喷丸)对电弧镀Al Cr N涂层表面进行处理,利用XRD、SEM、OM、摩擦磨损以及切削试验分析不同后处理方式对涂层组织结构、表面形貌、表面粗糙度、摩擦磨损以及切削性能的影响。结果显示:不同后处理方法均可有效清除Al Cr N涂层表面颗粒,其中湿喷砂、微粒子喷丸和干喷砂对涂层表面颗粒数目去除效果较好,"大颗粒"分别降低了91.1%、88.5%和86.9%,离子刻蚀后处理次之,颗粒数目降低了21.0%。经处理的Al Cr N涂层的XRD图谱与未处理的涂层相比没有明显变化,均为固溶(Al,Cr) N相,但其衍射峰均向低角度偏移。经过后处理涂层的摩擦因数相比于未处理的涂层均有不同程度降低,涂层磨损方式为磨粒磨损并伴有少量的氧化磨损。Al Cr N涂层刀具经过后处理工艺处理后,切削寿命均有不同程度提高,与未处理涂层刀具相比较经微粒子喷丸、干喷砂、离子刻、湿喷砂后处理的涂层刀具切削寿命分别提高了30%、40%、40%和60%。

Effects of Different Post-treatments on Structures and Properties of AlCrN Coating

There are number of " micro-particles" on the surface of the arc ion plated AlCrN coatings, which resulted in the high surface roughness, and decreased the friction, wear and cutting performance. In this paper, the AlCrN coatings were treated by different post-treatments including ion etching, wet sandblasting, dry sandblasting, and shot peening. XRD, SEM, OM, friction and wear, and cutting tests were used to examine the effects of post-treatments on phase, surface roughness, friction and wear, and cutting performance. The results showed that these four post-treatment methods could significantly remove the " micro-particles" . Among them, wet sandblasting, shot peening and dry sandblasting had better effect on clearing the " micro-particles" , and the number of " micro- particles" were reduced by 91. 1%, 88. 5% and 86. 9%. While, ion etching could only reduce the " micro-particles" by 21. 0%. The XRD patterns of the AlCrN coatings revealed the solid solution (Al, Cr)N phase, and all the diffraction peaks of the AlCrN coatings shifted to a low angle. The coefficient of friction of the post-treatmented coating reduced as compared with the untreated coating; the wear mechanism of the coatings were abrasive wear with a small amount of oxidative wear. The cutting life of the coated tools after various post-treatments have been improved, and cutting life increased by 30%, 40%, 40% and 60% for the AlCrN coating after shotpeening, dry sandblasting, ion etching and wet sandblasting treatments.