馆藏金属器物上浅蓝色铜锈蚀物的辨别与成因分析

不同于新出土青铜器上的锈蚀物,博物馆藏金属器物上经常可见浅蓝色铜的锈蚀物。为辨别和探析其成因,通过采用扫描电子显微镜-能谱仪(SEM-EDX)、X射线衍射仪(XRD)和激光拉曼光谱仪(Raman)进行元素成分和物相综合分析,发现其为铜的有机盐。这些有机盐包括简单(或碱式)的甲酸铜和乙酸铜,也包括复杂的含有钠离子和碳酸根的乙酸铜NaCu(CO₃)(CH₃CO₂)、含有钠离子和氧离子的水合甲酸铜Cu₄Na₄O(HCOO)₈(OH)₂·4H₂O。这种浅蓝色铜的有机盐形成根源主要有两种:储存或展览环境的不当;用于除锈的化学试剂的残留。要杜绝这类锈蚀物的形成需要确保储存和展览器物的环境低湿度且无有机酸释放材料的存在。对经过化学处理的器物应确保将化学试剂清理干净且无任何残留以绝后患。对复合材料器物的处理更应谨慎,因为对不同材质的处理和保存环境要求不一样,要个例对待。     

DAMAGE ASSESSMENT AND PRESERVATION OF AN EGYPTIAN SILVER VASE (300–200 BC)*

An Egyptian metal vase from the Ptolemaic period was investigated metallurgically and fractographically. The metal is nearly pure silver. Despite its high purity (in archaeological terms) it is severely embrittled and cracked, mainly along grain boundaries. Factors contributing to this damage are work-hardening and residual microstructural deformation (slip and twinning), corrosion along slip lines and twin boundaries, corrosion in bauds that are the remains of coring, large equiaxed grains, externally applied forces and internal residual stresses. The metal is now friable. This must be taken into account during any further restoration of the vase: a procedure is suggested.     

铜离子对纸张的腐蚀降解作用综述

绿色含铜颜料是书籍和艺术品中重要的着色物质,一些含铜化合物颜料例如铜绿,随着时间的推移,自身会发生明显褪色,随之引发载体纸张材料的损坏,腐蚀降解纸张。铜离子与纤维素间反应机理是氧化、催化、酸化水解和光化学作用等复杂反应机理的综合,对损伤后纸张的保护修复要在了解腐蚀机理的基础上运用去酸或者络合金属离子等缓蚀方法处理。结合国内外文献和现有研究工作对此进行了梳理和综述,提出了6点今后值得进一步研究的方向。希望该综述能为纸质文物保护工作者开展相关研究时提供思路和借鉴。     

荥阳小胡村墓地出土部分铜器的科学分析

小胡村墓地为殷墟晚期"舌"氏家族墓地,为探讨其出土铜器的腐蚀特征,揭示其所蕴含制作技术和相应考古学信息,从而为器物保护修复提供科学依据,采用金相显微镜和扫描电镜及能谱仪对墓地出土12件铜器进行基体锈层结构和制作技术分析研究。研究表明,相较纯铜、铜锡和铜锡铅合金,铜铅合金耐腐蚀能力较弱,腐蚀严重;铜器经冷热加工处理易造成内部组织结构不均内应力残存,间接加速铜器腐蚀;12件铜器材质:纯铜2件、铜铅合金4件、铜锡合金3件和铜锡铅合金3件;仅2件兵器(刀M28:1、戈M38:1)经有意铸后热锻和冷加工,其余皆直接铸造成型。M21墓4件铜器皆为铜铅合金明器,小胡村墓地作为殷墟周边商文化系统,趋同商文化中心区,亦呈现部分中小贵族随葬铜器明器化现象。研究结果可为器物修复保护提供科学依据。     

化学镀与电刷镀技术在鎏金铜器修复中的应用研究

为研究化学镀与电刷镀技术在鎏金铜器修复中的应用,使用扫描电镜、X射线衍射等测试方法对样品进行实验。结果发现在模拟补配材料的样品上镀覆效果良好,并对一件有残缺的鎏金铜器实施茬口清理、补配、化学镀、电刷镀等保护修复技术处理,完成一件器物独立配件的制备。修复后器物形态完整,外观和谐,再现了器物的美学价值。     

UNIQUE PRE‐ROMANESQUE MURALS IN KOSTOĽANY POD TRÍBEČOM,SLOVAKIA: THE PAINTING TECHNIQUE AND CAUSES OF DAMAGE

Pre‐Romanesque murals at Kosto?any pod Tríbe?om, Slovakia, have been investigated by portable X‐ray fluorescence and by microanalytical methods to identify painting materials (pigments and binders), and to explain the degradation of colours. Today, missing green and blue shades have been reconstructed according to residual concentrations of Cu, which correspond to copper chlorides—products of salt corrosion of the copper carbonates azurite and/or malachite, accelerated by micro‐organisms. As confirmed by powder X‐ray microdiffraction, original minium (Pb₃O₄) has been transformed to brown–black plattnerite (PbO₂). In increased humidity, even insoluble pigments are washing down from the walls and the intensity of colours further diminishes.     

应用电位活化理论研究青铜器的腐蚀与保护(二)——关于多孔氧电极的加速腐蚀机理研究

为了探讨铜盐等腐蚀产物对青铜器腐蚀的影响,采用腐蚀膏试验和微电极测试腐蚀电流的方法研究了氯化亚铜、碱式氯化铜、碱式碳酸铜等对青铜试片和铜电极腐蚀的影响,得出氯化亚铜是加速青铜器腐蚀的最有害物质的结论。红外光谱分析表明,以苯骈三氮唑为主钝化剂的高效防护剂同时改变了氯化亚铜的结构,起到了有效抑制青铜器腐蚀的作用。应用电位活化理论阐述了青铜器粉状锈小孔腐蚀的电化学行为,提出了氯化亚铜加速青铜器腐蚀的多孔氧电极催化模型。     

LA–ICP–MS,SEM–EDS AND EPMA ANALYSIS OF EASTERN NORTH AMERICAN COPPER‐BASED ARTEFACTS: IMPACT OF CORROSION AND HETEROGENEITY ON THE RELIABILITY OF THE LA–ICP–MS COMPOSITIONAL RESULTS*

This study discusses the relevance of compositions obtained using laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) for the purpose of identifying the provenance of copper‐based artefacts found in Virginia at Native American sites dated from the 16th to the 18th centuries. Ten artefacts were investigated by scanning electron microscopy – energy dispersive spectrometry (SEM–EDS) to visualize the corrosion and characterize the heterogeneities in the metal and electron probe micro‐analysis (EPMA) to determine separately the compositions of the intact metal and of the corrosion product. It is shown that the corroded surfaces are highly depleted in zinc but that representative concentrations can be determined by sampling the deeper, uncorroded metal. In contrast, lead values are highly variable because of the heterogeneous distribution of this metal within the bulk copper. Despite these problems, brass is easily identifiable and American native copper and European smelted copper can be unambiguously distinguished with LA–ICP–MS on unprepared artefacts using As, Ag, Ni and Sb trace elements.     

中国钱币博物馆部分陈列银币、铜币的腐蚀产物及成因研究

为探讨部分陈列银币、铜币腐蚀产物及其成因,采用三维视频显微镜、扫描电镜-能谱(SEM-EDS)、X射线荧光(XRF)、X射线衍射(XRD)等方法,对中国钱币博物馆部分遭受腐蚀的展陈钱币的腐蚀产物进行了分析,并通过红外光谱(FT-IR)对展陈材料进行了分析,最后对硫的来源进行了初步分析。结果表明,银币和铜币的腐蚀产物均含有硫化物,银币(银铤)的腐蚀产物为硫化银,铜币的腐蚀产物中主要为铜的硫化物,此外还含有铜的氧化物。经分析,展柜中的黏合剂氯丁胶在光照和较高温湿度条件下能分解并释放出硫化氢气体,因而初步判断银币或铜币的腐蚀产物是由于展柜内材料产生的硫化氢与银币或铜币反应生成。     

Management of Historic Shipwrecks Through a Combination of Significance and Conservation Assessments

Abstract

Corrosion modelling of decay rates of the iron wrecks in Port Phillip Bay, Victoria, has enabled an estimation of the speed at which the historic resource of iron shipwrecks is disappearing. Use of the significance ranking of the iron wrecks, based on the Australian National Standards for significance assessment, provides a useful guide to decision-making, but decisions based solely on these criteria can lead to less than optimal results. From the corrosion rates and the amount of residual metal thickness in structural elements it is possible to determine a conservation ranking that is based on the need for intervention and the chances of being successful in stabilizing the wrecks. The arithmetic product of the significance and conservation rankings defines the treatment score or ranking which forms the basis for rational decision making about deployment of resources.     

EARLY USE OF BRASS IN SILVER ALLOYS

Summary. The routine analysis of twenty-two silver rings revealed that in some Roman rings brass had been added instead of pure copper. These alloys had formed corrosion products during burial, which meant that the results of surface XRF analysis had to be used with caution. Destructive analysis gave accurate interior compositions, which are used in comparisons with similar material from other authors.     

铜片除锈强度考察与缓蚀效果分析

在青铜器除锈过程中,既要除去有害锈及其他杂质,又不损伤青铜器原貌,这就需要掌握一定的度。本研究用失重法定量地考察了不同除锈法和不同除锈剂对铜钱的除锈强度。结果表明,物理除锈法与化学除锈法均有明显的失重率。化学除锈中,5%左右的冰醋酸有较高的除锈强度。采用不同组合的BTA缓蚀剂对铜片进行保护,通过Tafel曲线分析其保护效果,以1.5%浓度的BTA与2%H_2O_2的组合液缓蚀效果明显。经盐雾腐蚀试验对此结论进行了验证。     

宝鸡眉县出土27件窑藏青铜器锈蚀特征及成分的分析研究

为了研究刚出土的青铜器在新的环境中的发展变化情况,在宝鸡眉县27件国宝级西周窖藏青铜器出土一年半后,对这批器物出土前后的锈蚀类型及特征进行了分析和描述,并对每一器物的锈蚀产物进行了系统检测分析。结果显示,这批青铜器腐蚀类型主要为封闭环境中的大气腐蚀,主要产物为碳酸盐和氧化物。但同时在其中一个器物上发现了氯化物类有害锈成分,分析认为,出土前后环境的变化是有害锈得以产生和发展的根本原因。     

天然氧化铜矿与铜制品腐蚀产物区别的探讨

在一些新石器时代的遗址中经常会出现一些铜渣、小块孔雀石等与炼铜有关的遗物。为探究这些孔雀石到底是天然的氧化铜矿还是铜制品的腐蚀产物,本工作对天然氧化铜矿和青铜器腐蚀产物进行岩相分析和元素成分分析。结果表明,天然氧化铜矿大都具有一些特殊的结构构造,而在铜制品的腐蚀产物中却很难发现这些结构构造;同时,二者在元素成分上也有显著不同,Bi、Sb、As、Fe、Mo、Co、Mn等微量元素可以作为区分天然氧化铜矿和青铜器腐蚀产物的一个判别标志。结合岩相分析和成分分析,可以确定一个遗址出土的孔雀石或蓝铜矿是天然氧化铜矿还是铜制品的腐蚀产物;同时,可进一步判断是红铜的腐蚀产物还是青铜的。这一结论对探讨铜冶金的起源有重要意义。     

两件秦代铅钡玻璃腐蚀特征研究

铅钡玻璃是我国特有的玻璃体系，主要集中在战国至两汉时期。随着越来越多的铅钡玻璃完整器被发现，相关的风化腐蚀研究和保护工作逐渐展开。本研究以陕西临潼新丰秦墓和河南三门峡秦墓出土的两件秦代(公元前221—公元前207)铅钡玻璃为样本，采用光学显微镜、扫描电子显微镜、激光拉曼光谱仪对铅钡玻璃的腐蚀层进行成分与结构分析，结果表明铅钡玻璃腐蚀层的钡大部分流失至环境或腐蚀层外侧，腐蚀层的主要物相为碳酸铅。腐蚀层的形成与铅钡玻璃埋藏环境中水位和酸碱度的周期性变化有关。本研究对铅钡玻璃保护工作具有参考价值，也为古代玻璃文物的预防性保护提供了有益的信息。     

Electrochemical Characterization and Dating of Archaeological Leaded Bronze Objects Using the Voltammetry of Immobilized Particles

The application of solid state electrochemistry techniques for the characterization and dating of leaded bronze objects is described. Characteristic voltammetric signatures of copper and lead corrosion products were used as markers of more or less prolonged corrosion periods. The proposed methodology was applied to samples from the Roman archaeological sites of Valeria (Spain) and Gadara (Jordan), Roman and medieval sites in Xàtiva (Spain), and modern statuary exhibited outdoors, on the campus of the Universitat Politècnica of Valencia, Spain, covering a time interval between the fourth to second century bc and the 20th century ad . For such samples, the ratio between the signals for copper and lead corrosion products decreased monotonically with the corrosion time. This variation was modelled on the basis of thermochemical and kinetic considerations, the experimental data being consistent with a potential rate law for the corrosion process.     

Managing a Monitor — the Case of HMVS Cerberus in Port Phillip Bay: Integration of Corrosion Measurements with Site Management Strategies

Abstract

The hull of the former HMVS Cerberus (1926) collapsed two metres during gales in December 1993, leaving the vessel half-submerged. Sunk as a breakwater in 1926, the vessel is one of the few remaining and accessible twin-turret Monitor-style warships from the 1870s. This paper presents the complex history of attempts to stabilize the site and to preserve the wreck. A series of in situ corrosion studies of corrosion potentials, pH, and residual metal thickness have provided a special insight into the processes of decay and have paved the way for future site stabilization. Removal of the four 16-tonne 10 inch Armstrong rifled muzzle loading guns and their in situ treatment alongside the wreck have assisted in relieving some of the stress on the remaining structure. The paper reports on correlations between the corrosion rate and the formation of concretions and how to determine the end point of an in situ treatment for cannon.     

高青陈庄遗址M35、M36出土青铜器腐蚀特征分析

高青陈庄遗址M35、M36出土的青铜器具有黑色锈蚀等特殊的腐蚀现象。本研究在对这两个墓出土青铜器腐蚀现象统计分析的基础上,对其典型的腐蚀特征进行了总结,并进行了相应的科技检测分析。得知,这两个墓葬土壤中可溶性硫酸盐的含量很高;青铜器中含有大量的S;其黑色腐蚀产物为铜硫化物;闪亮颗粒物为结晶良好的铜硫化物,晶粒为平行的板片状集合体;含有大量的“铜”,纯铜颗粒和纯铜片的显微结构形貌与铜硫化物相同;铜器所带有的绿色调和绿色锈点为硫酸盐矿物结晶所致;基体表层黄白、灰白色锈蚀中含有铜锡合金;铜器很少检测出氯离子。     

铁器文物脱盐清洗溶液中硅酸盐缓蚀性能的研究

硅酸盐是一种环保型的缓蚀剂,研究水溶液中硅酸盐与铁表面氧化物的相互作用对铁器文物脱盐清洗液的实际应用有较大的指导意义。本工作研究了羟基氧化铁对硅酸盐的吸附作用以及多种因素对Fe/FeOOH/Na_2SiO_3体系电化学行为的影响,并运用XRD技术分析研究了硅酸盐水溶液处理对钢铁表面氧化物形态的影响。结果表明,在Fe/FEOOH/Na_2SiO_3体系中,硅酸盐吸附在钢铁表面羟基氧化物上,反应生成了新的物质,形成了较为致密的缓蚀膜,可同时抑制钢铁的阴、阳极反应,且对阴极反应的抑制作用较强。     

Investigation of a Copper-based Hoard from the Megalithic Site of al-Midamman,Yemen: an Interdisciplinary Approach

In 1997, a hoard of copper-based objects was discovered at the megalithic site of al-Midamman, on the Red Sea Tihama coastal plain of the Republic of Yemen. Since there have been very few metal artifacts discovered in the lowlands of Yemen, and there was limited stratigraphy on the site, determining the time and place of production for these artifacts was difficult. A full investigation of the objects was deemed essential to determine their chronology and origin. Analysis included optical microscopy and scanning electron microscopy (SEM) for metallography, inductively coupled plasma spectrography (ICP) for bulk chemical composition, SEM to determine phase composition and corrosion products, and X-ray diffraction (XRD) to identify corrosion products.The objects can be divided into three types of copper and copper alloy: pure copper, arsenic rich copper, and tin rich copper. The difference in composition appears likely to be deliberate and suggests that the objects were produced sometime during the Early Bronze Age through the Middle Bronze Age. Further investigation of any metal objects discovered along the Yemeni coast and along the Ethiopian/ Eritrean side of the Red Sea is obviously essential.