处理面积对AZ31B镁合金微弧氧化负载特性的影响  

Effect of sample area on load characteristics of AZ31B magnesium alloy treated by micro-arc oxidation

作　　者：王晟[1] 黄志杰 兰晔峰[1] 刘康康 王小龙[1] 马颖[1] WANG Sheng;HAUANG Zhi-jie;LAN Ye-feng;LIU Kang-kang;WANG Xiao-long;MA Ying(State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals, Lanzhou Univ. of Tech., Lanzhou 730050, China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,甘肃兰州730050

出　　处：《兰州理工大学学报》2020年第5期7-12,共6页Journal of Lanzhou University of Technology

基　　金：甘肃省创新基地和人才计划-青年科技基金计划(17JR5RA112)。

摘　　要：为了明确处理过程中试样面积对微弧氧化负载特性及膜层性能的影响,采用单极性脉冲电源模式,对4个具有不同面积的AZ31B镁合金试样进行微弧氧化处理.处理中采用LCR测试仪采集负载的等效电阻和等效电容值,用示波器记录负载的电压、电流波形,并用MATLAB对负载电压波形进行拟合,以研究试样面积对微弧氧化处理过程中负载特性的影响.结果表明:随着处理电压的升高,所有的负载等效电容都持续减小,等效电阻都持续增大,负载的放电时间常数不断增大,等效电阻的增大说明膜层厚度随处理电压的增高而不断增长.此外,随着处理面积的增大,相同电压下负载的等效电阻不断减小,负载电容不断增大,负载的放电时间常数不断减小,说明随着面积的增大,膜层的增长变慢,而且面积越大的试样,负载波形更接近于方波,因此对单极性脉冲的实用性越好.In order to clarify the effect of sample area on the load characteristics and film properties of micro-arc oxidation,four AZ31B magnesium alloy samples with different areas were treated by micro-arc oxidation in unipolar pulse power supply mode.In the treatment,the equivalent resistance and equivalent capacitance of the load are collected by a LCR tester,the voltage and current waveforms of the load are recorded by oscilloscope,and the load voltage waveform is fitted by using software MATLAB,so as to investigate the effect of sample area on the load characteristics in the process of micro-arc oxidation.Our results indicate that with the increase of treatment voltage,the equivalent capacitance of all loads decreases continuously,the equivalent resistance increases continuously,and the discharge time constant of the loads increases continuously as well.The increase of the equivalent resistance indicates that the thickness of the film increases with increase of the treatment voltage.In addition,with the increase of the treated area,the equivalent resistance of the loads decreases,the load capacitance increases,and the discharge time constant of the loads decreases either.This indicates that the growth of the film becomes slower with increase of the treated area,and the larger the treated area is,the closer the load waveform is to the square wave.Therefore,it is more practical for the unipolar pulses.The equivalent resistance of the loads can reflect the thickness of the film.

关 键 词：镁合金 微弧氧化 处理面积 负载特性 时间常数 

分 类 号：TG174[金属学及工艺—金属表面处理]