CAJ | 학술논문

以磷酸盐化学转化膜为研究体系,采用交流阻抗(EIS)及红外(FT-IR)分析方法及检测手段,研究陈化时间对AZ91D镁合金磷化膜性能的影响及磷化膜的腐蚀退化机制.研究发现(1) EIS图谱和FT-IR图谱对比结果表明陈化时间对AZ91D磷化膜层性能有影响,磷化膜经陈化72h后更稳定.(2)磷化试样在硼酸缓冲液中浸泡实验的EIS测试表明,磷化膜的腐蚀退化机制分3个阶段:浸泡初期,中期和后期.浸泡初期(5～10h),电解质缓慢向磷化膜渗入,且有少量电解质浸入内层界面;浸泡中期(30～70h),随着内层界面腐蚀反应的发生,腐蚀产物开始对外层晶体层产生破坏作用,使缺陷扩大,导致电解质开始大量进入到内层界面;浸泡后期(80～120h),内层腐蚀反应达到平衡,膜层电阻等各项参数不再改变.
이린산염화학전화막위연구체계,채용교류조항(EIS)급홍외(FT-IR)분석방법급검측수단,연구진화시간대AZ91D미합금린화막성능적영향급린화막적부식퇴화궤제.연구발현(1) EIS도보화FT-IR도보대비결과표명진화시간대AZ91D린화막층성능유영향,린화막경진화72h후경은정.(2)린화시양재붕산완충액중침포실험적EIS측시표명,린화막적부식퇴화궤제분3개계단:침포초기,중기화후기.침포초기(5～10h),전해질완만향린화막삼입,차유소량전해질침입내층계면;침포중기(30～70h),수착내층계면부식반응적발생,부식산물개시대외층정체층산생파배작용,사결함확대,도치전해질개시대량진입도내층계면;침포후기(80～120h),내층부식반응체도평형,막층전조등각항삼수불재개변.
The effect of aging time on the anticorrosive properties of phosphate coating in 3.5wt% NaCl solution and corrosion degradation mechanism of phosphate coating in boric acid buffer solution was investigated by electrochemical impedance spectroscopy (EIS),Fourier transform infrared (FT-IR) spectrum.The results showed that,(1) Comparing the results of EIS with that of FT-IR,the properties of phosphate coating was influenced by aging time,and the phosphate coating was more stable when the aging time exceeds 72h.(2) The degradation process of phosphate coating in boric acid buffer could be divided into three stages:the initial immersion stage,the medium-term and the later immersion.At the initial immersion stage (5-10h),the electrolyte infiltrated the crystal outer layer slowly;the structure of outer layer was unspoiled.At the medium-term (30-70h),defects of the crystal outer layer became to expanding for the detrimental effect of corrosion products,anticorrosive properties of the phosphate coating declined rapidly.Later immersion (80-120h),the corrosion reaction on the inner layer achieved balance,the electrochemical parameters such as resistance of coating was changeless.