• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2348-2352
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• 2013

We report a simple electrochemical approach in fabricating multiple colored molybdenum (Mo) oxide bronzes on the surface of a Mo-quartz electrode. A three step electrochemical batch process consisting of linear sweep voltammetry and anodic oxidation followed by cathodic reduction in neutral $K_2SO_4$ electrolyte at different end potentials, viz. -0.62, -0.80 and -1.60 V (vs. $Hg/HgSO_4$) yielded red, blue and yellow colored bronzes. The samples produced were analyzed by XRD, EDS, and SIMS. The color variation was suggested to be associated with the cations intercalation into the oxide formed and the simultaneous structural changes that occurred during the cathodic reduction in neutral aqueous medium.

• Korean Journal of Heritage: History & Science
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• v.51 no.4
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• pp.224-233
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• 2018

Thirty-three Early Iron Age bronzes at the sites of Hoam-dong in Chungju and Cheongsong-ri in Buyeo were investigated in order to study the manufacturing technique and the provenance of lead. Chemical analysis using X-ray fluorescence showed that 33 bronzes consist of copper(Cu), tin(Sn) and lead(Pb) served as major elements. Major and minor elemental analyses by EPMA were performed on two mirrors and 2 weapons of the bronzes investigated. The results shows that bronze mirrors from Chungju and Buyeo were high-tin bronzes(> 30 wt%). And 20% of tin and 5% of lead were founded in bronze weapons. Iron, zinc, arsenic, silver, nickel, sulfur and cobalt detected in four bronzes as minor and trace elements. The four bronzes were alloyed considering their function and were not heat treated after casting due to their high tin content. Lead isotope analysis using TIMS indicates that thirty-three bronzes were distributed southern Korea peninsula except Zone 1. As a result, lead raw materials came from various regions in Korean Peninsula not from Gyeongsang-do regions. The manufacturing techniques of bronze ware generalized at this age, and bronze was produced in various sites using raw materials from various sources.

• 보존과학연구
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• s.36
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• pp.4-10
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• 2015

This paper confirms characteristics of lead isotopes of bronze artifacts excavated from Korea peninsula using 673 data classified according to Age, type and region. Lead isotopes data in Early iron ages are distributed in the southern Korean peninsula, but data in Joseon ages are concentrated in zone 3. Also Bronze artifacts excavated from Seoul, Gyeonggi, Chungcheong, Jeolla and Gyeonsang are manufactured using raw materials of the entire Korea peninsula, but bronzes excavated from North Korea aren't produced using raw materials of Gyeonsang provinces. Lead isotopes data will be able to find moving routes of raw materials and to separate the period of mixing and recycling of lead.

• Korean Journal of Heritage: History & Science
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• v.46 no.3
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• pp.4-15
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• 2013

The study of corrosion products generated by archaeological bronzes that have been buried for a long time can provide certain evidence that enables us to understand the natural corrosion process of bronze and helps us develop conservation and preservation methods. In the present study, the specimens taken from two bronze mirrors and three bronze swords were used to study the corrosion morphology and the related phenomena such as selective corrosion of ${\alpha}$ or ${\alpha}+{\delta}$ phases, decuprification, destannification, and secondary copper. Furthermore, corrosion development was discussed based on the ions distributed throughout the corrosion layers.

• Journal of Conservation Science
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• v.35 no.3
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• pp.187-196
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• 2019

Bronzes excavated from a Gulsansa temple site in Gangneung were investigated in order to study the production of technology and provenance in this area. The bronze artifacts were discovered to consist of copper-tin or copper-tin-lead alloys using chemical analysis(EDS and EPMA). The excavated bronzes were manufactured using a casting or hammering process, and a bronze belt was gilded with gold foil. The provenance of 25 bronzes was studied using lead isotope analysis(TIMS and LA-MC-ICPMS). The results reveal the use of raw materials found near the excavated site. The object of this study was to investigate the manufacturing techniques and provenance in Gangneung without the need for a lot of data. Our results will contribute to the study of Gulsansa and bronze artifacts in Goryo(12-13th century).

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.60-65
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• 2004

[ $MoS_2S$ ] is a well-known metal sulfide applied as solid lubricants and an additive to prolong the life of sintered bearings under severe conditions. However, the high price of $MoS_2S$ limited its wide application. This study is aimed to investigated the possibility for application to solid lubricants for $Cu_2S$ as a substitute of v. Bronzes added $Cu_2S$ and $MoS_2S$ are produced by powder metallurgy in this study, and then evaluated their friction and wear properties. The sliding wear test using pin-on-disc type machine, was conducted at several sliding speeds for three type test pieces, bronze and bronzes added $Cu_2S/MoS_2$. Addition of $Cu_2S$ to bronze leads to relatively good friction and wear properties, although it is not so good as addition of $MoS_2S$. But the properties of bronze added $Cu_2S/MoS_2$ would be not suitable for the condition under the high sliding speed.

• Tribology and Lubricants
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• v.23 no.2
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• pp.66-72
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• 2007

[ $MoS_2$ ], is a well-known metal sulfide applied as solid lubricants and an additive to prolong the life of sintered bearings under severe conditions. However, the high price of $MoS_2$ limited its wide application. This study is aimed to investigate the possibility far application to solid lubricants for $Cu_2S$ as a substitute of $MoS_2$. Bronzes added $Cu_2S$ and $MoS_2$, are produced by powder metallurgy in this study, and then evaluated their friction and wear properties., as well as sintered bronze. The sliding wear test using pin-on-disc type machine, was conducted at several sliding speeds for three type test pieces sintered bronzes added $Cu_2S$ and $MoS_2$, and sintered bronze without lubricants. Addition of $Cu_2S$ to bronze leads to relatively good friction properties, although it is not so good as addition of $MoS_2$. However, the wear properies of sintered bronze added $Cu_2S$ are better than that of sintered bronze added $MoS_2$.

• Advances in materials Research
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• v.2 no.4
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• pp.221-235
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• 2013

To obtain bronze with good mechanical properties and high wear resistance, a new bronze (CADZ) is proposed on the basis of various fundamental information. The CADZ consists of the elements Al10.5, Fe4.2, Sn3.7 and Ni3.1, and its design is based on Cu-Al10.5 alloy. The Cu-10.5%Al is very hard and brittle. To obtain the high material ductility of the Cu-10.5%Al alloy, an attempt was made to add a few percent of Sn. Moreover, to make high strength of the Cu alloy, microstructure with small grains was created by the proper amount of Fe and Ni (Fe/Ni = 0.89). The mechanical properties of the CADZ sample have been examined experimentally, and those were compared with commercial bronzes. The tensile strength and wear resistance of CADZ are higher than those for commercial bronzes. Although the ductility of CADZ is the lower level, the strain to failure of CADZ is about 2.0~5.0% higher than that for the Cu-Al10.5 alloy. Details of the microstructural effects on the mechanical properties in the CADZ sample were further discussed using various experimental results.

• Journal of Conservation Science
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• v.26 no.2
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• pp.109-120
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• 2010

Four gilded bronze objects and a gilded silver object were examined for elemental diffusion between the gilding layer and the mating matrix. The gilded bronzes consist of three objects from three different historical periods, the Korean Three Kingdoms period, the Koryo and the Choseon periods and one from an unknown period. The gilded silver was from the Koryo period. The amalgam process seems to have been the major technique employed for all of them in gilding. The occurrence of substantial diffusion was observed in all but the anonymous object, particularly in the Choseon artifact where evidence was found that the diffusion phenomenon was intentionally utilized in gilding. The gold content in the gilded bronzes decreases gradually from surface to interior while the copper content increases to the interior, making it difficult to locate the boundary between the gilding layer and the matrix. This gradual change in composition must have resulted from elemental diffusion at elevated temperatures. The oxygen content negligible in the gilding layer precludes the possibility of corrosion being responsible for the varying composition. It is observed that non-uniform diffusion caused variation of colors in the surface of gilded bronzes. The change of colors induced by diffusion, which is always accompanied by the unique surface morphology and chemical compositions, is distinguished from the color change by corrosion. In the gilded silver object, diffusion of mercury was observed along with that of gold and silver.

• Korean Journal of Heritage: History & Science
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• v.48 no.2
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• pp.110-119
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• 2015

Bronzes, Earthenwares and various artifacts were excavated from Pungnap earthen fortress in the early Baekje age in Korea. This study was performed in order to identify the manufacture technology of bronze artefacts and provenance of lead in bronzes. Microstructure and chemical composition results show that 3 of them are Cu-Sn-Pb alloys in which an intentional lead addition was carried out and one is tin bronze showing straight twin structure within crystal grains. Also $CuFeS_2$ or $Cu_5FeS_4$ was used as raw materials through the detection of S and Fe as trace elements. The lead isotope results could be matched with one of the zones of southern Korea and China on the East Asian map. This results shows that data were plotted either in zone 2 or zone 3 of the South Korean galena map. However, one of bronze artifacts was matched with the zone of Northern China.