已锈蚀青铜在大气环境中的腐蚀发展及其保护研究

CORROSION BEHAVIOR OF PATINATED BRONZE AND ITS PROTECTION IN ATMOSPHERE

用动电位扫描法和循环伏安实验对青铜文物在模拟大气环境介质0.028 mol/L NaCl+0.01 mol/L Na2SO4+0.016 mol/L NaHCO3中的电化学行为进行了研究,探讨了CuCl、Cu2O、碱式氯化铜、混合锈对裸青铜的保护作用.结果表明:在腐蚀电位较负时,Cu2O、CuCl对基体有一定的保护性,而且保护性能优于碱式氯化铜和混合锈;在腐蚀电位较正时,Cu2O或CuCl对青铜的保护性变差,而此时碱式氯化铜和混合锈对裸青铜的保护性优于Cu2O、Cu-Cl.0.1%MBO(2-巯基苯并恶唑)酒精溶液对裸青铜或被Cu2O、CuCl覆盖的青铜阳极过程有一定的抑制作用,对被碱式氯化铜或混合锈覆盖的青铜阳极过程有优异的抑制作用.

Potentiodynamic scanning methods and cycle voltammetry （CV） technique were employed to study the electrochemical behavior of archaeological bronze in a medium （0. 028 mol/L NaCl ＋ 0.01 mol/L Na2SO4 ＋ 0. 016 mol/L NaHCO3） simulating atmosphere corrosion. The study focused on the protection performance provided by CuCI, Cu2O, Cu2（OH）3Cl and mixed patina to bare bronze, and the results are that when the corrosion potentials are relatively negative, CuCI and Cu2O respectively exibibit to be protective to bare bronze to certain extent, and they perform more effective than that of Cu2（OH）3Cl or mixed patina＇ s. On the other hand when the corrosion potentials are relatively positive the protectiveness of CuCI or Cu2O to bare bronze turn to poor and Cu2（OH）3Cl or mixed patina exhibit better protective to bare bronze than that of CuCI or CueO. The 0.1%MBO （2-Mercaptobenzoxazole） alcohol solution can suppress anodic reactons of bare bronze or bronze covered with CuCl or Cu2O to some extent and can obviovsly suppress that of bronze covered with Cue （OH）3Cl or mixed patina.