脉冲频率对7050高强铝合金微弧氧化膜层的影响

Under the conditions of pulse frequencies of 50, 250, 500, 750, and 1000 Hz, ceramic film layers were prepared on the surface of 7050 high-strength aluminum alloy by applying micro-arc oxidation (MAO) technology. And the surface morphology, phase composition, corrosion resistance, wear resistance, etc. of the ceramic films were analyzed by means of scanning electron microscope (SEM), X-ray diffractometer (XRD), electrochemical workstation, friction and wear testing machine, etc. The results show that when the pulse frequency is too low, the surface of the MAO ceramic film layer is rough, affecting the compactness of the film layer; while when the pulse frequency is too high, it is not conducive to the growth of the MAO ceramic film layer, and the obtained film layer has poor corrosion resistance and wear resistance. When the pulse frequency is 250 Hz, the prepared film layer has the best wear resistance and corrosion resistance.

在脉冲频率为50、250、500、750、1 000Hz的条件下,应用微弧氧化(MAO)技术在7050高强铝合金表面制备了陶瓷膜层,并采用扫描电镜(SEM)、X射线衍射仪(XRD)、电化学工作站、摩擦磨损试验机等手段分别对陶瓷膜的表面形貌、相组成、耐腐蚀性、耐磨性等进行分析。结果表明,当脉冲频率过低时,MAO陶瓷膜层表面粗糙,影响膜层致密性;而当脉冲频率过高时,则不利于MAO陶瓷膜层生长,所得的膜层耐蚀性和耐磨性较差。当脉冲频率为250Hz时,所制备的膜层具有最佳的耐磨性及耐蚀性。