汉代铜镜显微组织腐蚀现象的比较分析——以安吉上马山及临淄出土为例

Comparative analysis of the microstructural corrosion phenomenon of the Han Dynasty bronze mirrors from Shangmashan and Linzi

利用体式显微镜、金相显微镜及扫描电镜-能谱对17面浙江安吉上马山及山东临淄汉代铜镜进行取样观察、检测,对二者进行比较分析。结果表明,上马山铜镜表面保存状况较好,类似黑漆古,内部为α相优先腐蚀,临淄铜镜表面腐蚀严重,为Cu_2O与二价铜的碱式矿化物沉积,内部主要为δ相优先腐蚀。利用Pourbaix图可以对两类腐蚀现象所处环境进行讨论,结果表明高锡铜镜基体在不同环境中存在α相或δ相优先腐蚀的现象,并与基体外部不同锈蚀相对应。此结果对研究不同环境中高锡青铜基体的微观及宏观腐蚀情况有参考价值。

We have done a comparative analysis of samples selected from 17 Han dynasty bronze mirrors from Shangmashan in Anji,Zhejiang Province and Linzi,Shandong Province,using a combination of stereo,metallographic and scanning electron（ with energy dispersive spectrometry） microscopy. The results show that 1） the surfaces of the bronze mirrors from Shangmashan are better preserved（ similar to ＂Heiqigu＂,ancient bronzes with dark protective layers like black lacquer）,with preferential corrosion of the α-phase in the inner layer; 2） the bronze mirrors from Linzi have heavy surface corrosion,with deposition of cuprous oxide and basic cupric minerals outside and preferential corrosion of the δ-phase inside. Pourbaix diagrams were used in the analysis and discussion of the environments of these two corrosion phenomena. It appears that the preferential types of corrosion seen in the α-phase and the δ-phase in the inner layer of high tin bronze mirrors seen in different environments are related to the different corrosion products outside.