• 한국문화재보존과학회:학술대회논문집
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• 2003.09a
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• pp.73-74
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• 2003

• Journal of Conservation Science
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• v.5 no.2 s.6
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• pp.35-44
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• 1996

We propose a new method to remove salts that have permeated into excavated metal objects. This method cleans the excavated metal objects by using high temperature, high pressure deoxvgenated water containing inhibitors for corrosion of metals. The method greatly reduces the washing time compared with previous methods. Waste water from the method does not need treatment, nor do chemicals need to be removed from the metal objects. Furthermore, this method is applicable to some kind of metals(for example iron objects, bronze objects). We measured quantitatively the soluble salts dissolved from actual metal objects and found that there was a large difference between soluble chloride ions and sulfate ions.

• Conservation Science in Museum
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• v.17
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• pp.55-68
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• 2016

Conservation and research efforts are currently underway at the National Museum of Korea on a series of artifacts excavated from Tomb No. 9 at Seogam-ri nearly a century ago by an archaeology team from the institution's colonialera predecessor. Among these objects are a number of bronze and gilt bronze buttons. The present study explores the production techniques used in making such buttons. Both bronze and gilt bronze buttons are hemispherical in shape and are similar in external appearance. However, their shanks differ significantly in size and cross-sectional shape, some with a round cross-section while others are square. The buttons, first sorted into two groups by each type of shank, were further subdivided by size. Analysis of round shanks has found variations in design and location as well as in shank thickness. In addition, the location where round shanks attach to buttons are usually irregular in surface. Square shanks, on the other hand, are more uniform in design and location. The shanks are typically located on the backs of buttons and attach to a groove which ostensibly serves to mark the correct position. X-ray imaging has revealed that round shanks have thick borders made from metal rather than dirt or other material. The buttons themselves appear to been cast using lost-wax technique. The ways in which each shank attaches to its respective button varies based on its cross-sectional shape.

• Korean Journal of Heritage: History & Science
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• v.46 no.1
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• pp.208-227
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• 2013

Twenty-seven bronze bowls excavated from the Goryo burial complex at Deobu-gol were examined for their microstructure and chemical composition to characterize the bronze technology practiced by commoners at the time. Results showed that the objects examined can be classified into four groups: 1) objects forged out of Cu-near 22%Sn alloys and then quenched; 2) objects cast from Cu-below 10% Sn alloys containing lead; 3) objects cast from Cu-10%~20% Sn alloys containing lead and then quenched; 4) objects forged out of Cu-10~20% Sn alloys containing lead and then quenched. This study revealed that the fabrication technique as determined by alloy compositions plays an important role in bronze technology. The use of lead was clearly associated with the selection of quenching temperatures, the character of inclusions and the color characteristics of bronze surfaces. It was found that the objects containing lead were quenched at temperatures of $520^{\circ}{\sim}586^{\circ}C$ while those without lead were quenched at the range of $586^{\circ}{\sim}799^{\circ}C$. The presence of selenium in impurity inclusions was detected only in alloys containing lead, suggesting that the raw materials, Cu and Sn, used in making the lead-free alloys for the first group were carefully selected from those smelted using ores without lead contamination. Furthermore, the addition of lead was found to have significant effects on the color characteristics of the surface of bronze alloys when they are subjected to corrosion during interment. In leaded alloys, corrosion turns the surface light green or dark green while in unleaded alloys, corrosion turns the surface dark brown or black. It was found that in fabrication, the wall thickness of the bronze bowls varies depending on the application of quenching; most of the quenched objects have walls 1mm thick or below while those without quenching have walls 1mm thick or above. Fabrication techniques in bronze making usually reflect social environments of a community. It is likely that in the late Goryo period, experiencing lack of skilled bronze workers, the increased demand for bronze was met in two ways; by the use of chief lead instead of expensive tin and by the use of casting suitable for mass production. The above results show that the Goryo bronze workers tried to overcome such a resource-limited environment through technological innovations as apparent in the use of varying fabrication techniques for different alloys. Recently, numerous bronze objects are excavated and available for investigation. This study shows that with the use of proper analytical techniques they can serve as a valuable source of information required for the characterization of the associated technology as well as the social environment leading to the establishment of such technology.

• 보존과학연구
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• s.16
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• pp.41-58
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• 1995

Several comparisons of treatment methods for stabilizing corroded Chinese coins at Shin-an marine sites were investigated. In aqueous solution, the seexamination were performed to show whether chloride ions are gradually removed, patination changes are acceptable and archaeological details are identified. The six desalting methods showed that the orders of removal of chloride ions were ranked electrolysis (electolyte : 0.1M sodium sesqui.)> 5% sodium dithionite(1M NaOH)> 5%sodium dithionite(0.1M sesqui.)> 5% citric acid> 0.1M sodium sesquicarbonate>deionized water. As the examinations of moisture absorption to the relative humidity has compared for bronze disease, all of desalted coins for the R.H 53% and R.H 75%except to R.H 95% are showed serious bronze disease.

• Journal of Conservation Science
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• v.27 no.4
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• pp.421-430
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• 2011

Thermal conditions in practice at the traditional bronze workshop of the Korean Folk Village in Yongin were examined along with the microstructures of some high tin bronze objects made there. Laboratory experiments approximating the conditions of the workshop were also carried out and the results were compared. The operating temperature of the workshop furnace was measured to range from $750^{\circ}C$ to $850^{\circ}C$ while the surface temperature of an object, upon its removal from the furnace for additional thermo-mechanical treatments, was generally in the range of $600^{\circ}C$ to $685^{\circ}C$. This variation in working temperatures was reflected in varying microstructures developed upon quenching. The products of the Folk Village were found to consist of microstructures where the ${\alpha}$ grains of the Cu-Sn system were distributed in the background of different phases including the ${\beta}$-martensite phase, retained ${\gamma}$ phase, ${\alpha}+{\delta}$ eutectoid or their mixtures. This variability, which is also identified in objects made in ancient times as well as in our laboratory experiments, suggests that the actual thermal conditions given during the quenching treatments are much more complicated than is inferred from the temperature measurements. This paper will present detailed accounts of the thermo-mechanical treatments as observed in the high tin bronze workshop of the Korean Folk Village and discuss the evolution of varying microstructures in terms of the substantial variability involved in the implementation of the traditional forged high tin bronze technology of Korea.

• Journal of Conservation Science
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• v.28 no.4
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• pp.403-410
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• 2012

The brine treatment applied during the fabrication of forged high tin bronze objects is considered effective at the removal of surface oxide layers developed at elevated temperatures. There is not much information, however, available for the understanding of its exact effect and purpose. This work performed laboratory experiments to characterize the effect brine treatments produce on the surface of bronze objects during fabrication. Specimens were first made in the bronze shop of the Yongin folk village under varying conditions of brine treatments, and the results obtained were then used in the following laboratory experiments where the effect of brine treatments were investigated in terms of brine concentrations, alloy compositions and thermo-mechanical treatments. The results show that oxide layers generated at high temperature are easily removed by the brine treatment. It was found that the element, chlorine, played a key role in the removal of such oxide layers as opposed to the other constituent of the brine, sodium, makes no notable contribution. In bronze alloys containing 22% tin, this brine effect is obtained regardless of the application of forging as long as the brine concentration is over 0.5% based on weight. In alloys containing lead, however, no brine effect is observed due to the molten lead that emerges from inside the hot bronze specimen and forms a thin layer on its surface.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.131-134
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• 2004

A lot of foreign objects(ceramics, pottery, bronze, glassware and coins, etc.) have been found in the archaeological sites in Korea. These foreign objects are the evidences of the cultural exchanges of that time, whose scale and routes are an important part of the studies in ancient history. So it is crucial to accumulate basic reference information such as the raw materials and the production method of these objects through scientific researches, along with archeological researches. These scientific research materials provide a basis for finding the importing route and the origin of these objects. Besides, we can find out extraordinary and distinctive production technique by comparison with tile domestic objects. This article reports the result of an analysis, performing on 36 samples of the glassware fragments excavated from the South Tomb of the Hwangnamdaechong, to verify their components and note peculiar features. We have analyzed the major and minor components of 10 elements, and then by using these data examined the differences in the composition of components, varying with the origin and color of glassware. We used the PCA(principal component analysis) as the statistical method to classify the sample in order to find out how the samples formed groups.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.137-153
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• 2004

We have analyzed the ingredients of 17 pieces of Bronze Age bronze ware, and an additional 22 pieces of Koryo and Chosun dynasty bronze ware. We have also conducted analysis of the extraction sites where these bronze ware items were found. For analyzing the main ingredient the bronze ware items have been divided into 3 groups - Cu-Sn(70?75:20), Cu-Pb-Sn(70:10:10), Cu-Pb-Sn(60:10:20) type respectively. In tile cases of the Cu-Pb-Sn groups the division comes down to differences in the Cu content as the main component, and elements such as Ni, Fe, Co contribute as a micro ingredient. The geographical and periodic characteristics of ancient bronze ware items show that theircompositional element changes from Cu:Sn to Cu:Pb:Sn and the Cu content decreases with the period,while the Pb content increases with the period. Bronze ware items from Suchon Ri, Gongju (that were used in 3 B.C.) form very different categories from 3rd ${\~}$ 2nd B.C.. They additionally formed very different categories from those bronze ware items analyzed in this research. These bronze ware itemsare shown to be geographically close and periodically overlapped, but made of a new elemental composition. This shows an inflow of a production technical culture present in the new bronze wares. The main component content of Cu is lower, and the Co and Fe contents (as microelements) are much higher than that of other bronze ware items. Such facts showthat those bronze ware items used completely different materials from bronze ware items in other cultural areas, or that there were differences in smelting techniques In the places where ancient bronze ware items have been extracted, it is presumed that the materials originated from the southern parts of Korea andnorthern parts and southern parts of China. .As more bronze ware scientific research is compiled one can conclude that that there will be enough scientific evidence to study the Bronze Age culture of Koreasystematically.

• 보존과학연구
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• s.31
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• pp.173-202
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• 2010

Within the framework of the Mongolian-Korean Joint Project for "Research and Preservation of Cultural Heritage", I enrolled in 3 months training course from February to May 2010 at the Metal laboratory of Conservation Science Division in National Research Institute of Cultural Heritage, Korea. Some metal artifacts, which are preserved in Institute of Archaeology, Mongolian Academy of Sciences, were brought and restored there. These chosen findings were found at Gobi and mountainous region of Mongolia, preserved under the different circumstances and dated back to Middle Age from Bronze Age. At the Metal laboratory of the NRICH, the conservation work was carried out for three months on 15 metal objects, including arrowhead, stirrup, caltrop, axe, knife, ring and so on, which were found at Khugshin Teel's ruin of Khairkhandulaan soum of Uvurkhangai province, Ungut of Altanbulag soum of Tuv province, Baruun Naran and Ukhaa khudag of Khankhongor and Tsogttsetsii soums of Umnugobi province. The report of the result of this conservation work is available here.