Effect of DC Mode Current Density on Properties of Micro-Arc Oxidation Film on Aluminum Lithium Alloy

In order to study the influence of electrical parameters on the film formation mechanism and film properties of aluminum-lithium alloy micro-arc oxidation in DC mode，2195 aluminum lithium alloy was used as the research object to prepare micro-arc oxidation ceramic film in a silicate phosphate alkaline electrolyte system under different current densities in a DC steady current mode.The surface and cross-sectional morphology， elemental composition and phase composition of micro-arc oxidation film were analyzed by scanning electron microscopy (SEM)，energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD).The corrosion resistance and wear resistance of different ceramic film were measured by using an electrochemical workstation and a friction and wear tester.Results showed that the ceramic film mainly contained O，Al， Si， and P elements， and the phase composition of the film layer was mainly γ-Al2O3 and a small amount of α-Al2O3.In the range of current density 4～16 A/dm2， with the increase of current densi