表面预制微槽对铸铝合金微弧氧化陶瓷膜结构和性能的影响

Effect of Surface Prefabricated Micro-groove on the Structure and Properties of Cast Aluminum Alloy Micro-arc Oxidation Ceramic Coating

为了探索表面预制微槽对铸铝合金微弧氧化陶瓷膜微观结构及性能的影响,在ZL108铝合金表面制备微弧氧化膜层,采用扫描电镜、X射线衍射仪、数字显微硬度计、多功能表面性能测试仪、电化学工作站等对膜层形貌及性能进行测试。结果表明:相比光滑试样形成的氧化膜层,微槽试样表面形成的膜层较厚、结合力较大,但由于微槽位置放电集中,能量过高,导致膜层多孔疏松,使硬度和耐蚀性降低;虽然表面微槽使得膜层质量略有下降,但其能提高微弧氧化放电能量,增加成膜速率。

In order to explore the influence of surface prefabricated micro-groove on micro-structure and properties of micro-arc oxidation ceramic coating of cast aluminum alloy,a micro-arc oxidation film was prepared on the surface of ZL108 aluminum alloy.Scanning electron microscopy,X-ray diffraction,digital microhardness tester,multi-function surface performance tester and electrochemical workstation were used to test the morphology and performance of the coating.The results show that compared with the coating formed on the smooth sample,the coating formed on the micro-groove sample was thicker and more rigid.However,due to the concentrated discharge at the micro-groove location and the high energy,the coating was porous and its adhesion and corrosion resistance were worse.Therefore,although the surface micro-groove makes the coating quality decrease slightly,it can improve the energy of micro-arc oxidation discharge and increase the coating formation rate.