| The high specific stiffness and strength alloys are widely applied in the field of aviation and navigation. In the corrosive media of rain and sea water, the behavious of friction wear and fatigue would markedly affect the mechnical properties, service life, and reliability. Titanium alloy and aluminum alloy are commonly used high specific alloys with low wear resistance. So the corrosion wear characteristics of the two alloys, both before and after surface modification, were investigated in present work simultaneously.The phase, surface image, thickness, and hardness of the film which modified by method of micro-arc oxidation (MAO) in LY12 and TC11were studied firstly. The corrosion fretting behavior of LY12, TC11 and their MAO-films were consequently investigated in air, distilled water, artificial sea water and rain water respectively by using the ball-on–flat configuration against 440C stainless steel ball with 300μm reciprocating amplitude. The potentiodynamic anodic polarization was used to study the corrosion behavior of the materials before and after the corrosion wear. The morphology and composition of the wear scars were observed and analyzed by using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). Elements valence in wear scars were also detected by X-ray photoelectron spectroscopy (XPS). 3D-morphology, profiles across the centre, and wear volume loss were determined by using a non-contact optical profilometer. The influences of load, frequency and media on the friction coefficient and wear volume of materials were analyzed.Results showed that both the friction coefficient and wear loss of the four kinds of materials in air were all much higher than those in the other three aqueous. Meanwhile, the wear characteristic in air, presented as oxidation and abrasion wear, is different from those in aqueous. So, the distilled water was selected as referrenced medium to study the corrosion-wear characteristic and their synergism between corrosion and wear. Some summaries obtained were listed as follows:As for LY12 aluminum alloy, lubrication films formed in seawater or rainwater can reduce the corresponding friction coefficient, but the specific wear rate increased due to the erosion effection of chlorin ion on the wear scar. The specific wear rate increased as following sequence: in distilled water, in rain, and in sea water, which demonstrate the positive synergism between corrosion and wear.As for TC11 titanium alloy, lubrication films formed in the two corrosive media reduced the corresponding friction coefficient, but the wear-loss presented different trends with different media and wear parameters. It was approved as slight positive synergism in rainwater and negative synergism in seawater when fretting corrosion was carried out. Further experiments showed that the negative synergism would weaken gradually as time goes by in the fretting corrosion, and it would change into positive interaction when amplitude increased from fretting scale to sliding in meter scale. It demonstrated the accelerating effection of frequency, duration, and amplitude on synergism between corrosion and wear.All the wear resistances of LY12 and TC11 in the four media were increased in different degree after MAO treatment, especially for MAO-LY12, which wear resistance in searwater was 7 times as much as that of original LY12. The corrosion-wear property was remarkably improved.The special anti-friction modulus k was introduced into current corrosion-wear model to modify the wear offset. Both positive and negative synergism can be perfectly explained by the modified model. Analyzed by the new model can be found that the synergism was enhanced as increasing of frequency, duration, and amplitude, which resulted in the increasing of the total wear-loss in corrosive medium.
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