• Korean Journal of Materials Research
• /
• v.20 no.2
• /
• pp.82-89
• /
• 2010

Benzotriazole (B.T.A) which has been mainly used for the stabilization processing method of excavated copper and bronze artifacts is vaporized within 2~3 years after the usage because it is unstable at the acid conditions and cannot protect the surface of artifacts. In this study, NaOH method which has been used for the steel artifacts was applied as a stabilization process for the method of copper and bronze artifacts to gush chlorine ion out. For the reproduction of excavated samples, copper and bronze plates were dipped in 0.1M HCl for 26 hrs to form CuCl, rusted at $70^{\circ}C$ with RH 75% for the formation of corrosion products, and desalted in 0.1 M NaOH solution. The concentration of chlorine ion was measured by using ionchromatography. During the desalting process, a large quantity of chlorine ions was gushed out in early period and corrosion products were not additionally generated through the re-corrosion experiment. This NaOH desalting process was found to be a method of stabilization process for copper and bronze artifacts from the formation of Tenorite (CuO) during desalting as a protection layer for corrosion.

• Journal of Conservation Science
• /
• v.1 no.1 s.1
• /
• pp.60-79
• /
• 1992

In relation to the scientific conservation treatment of ancient gilt bronze, the gold film coated on the bronze excavated from Hwangnam Great Tomb of Old Silla Kingdom(A. D. 5C) was studied in the view of coating technology and metallurgy of bronze. The uniform and dense gold film containing $2.44\sim12.40%$ of Hg with the thickness of $5.99\sim12.97{\mu}m$ was found to be coated on the bronze objects by amalgam coating method. On silver objects, the film with the thickness of $19.96{\mu}m$ was coated also continously and uniformly with gold by the same method. The bronze objects was fabricated by forging technique and contained almost $4.7\sim11.5%$ of Pb. Its microstructure was $\alpha-phase$ solid solution including Pb segregation in the matrix. The amount of $0.4\sim2.0%$ Zn was added in the bronze for the purpose of easy fabricating of Cu alloy. Based on the data studied, the gold film on bronze sample was reproduced by amalgam coating method and compared with the ancient gold film.

• Korean Journal of Heritage: History & Science
• /
• v.55 no.2
• /
• pp.24-48
• /
• 2022

Bronze mirrors found in pagodas were regarded as simple offerings and thus have received little attention in studies. Furthermore, the few studies on bronze mirrors enshrined in pagodas have focused on the line-engraved mirrors found in the pagodas of the Kingdom of Wuyue; therefore, it is difficult to understand the general characteristics of the bronze mirrors enshrined in the pagodas. This study assumes that the bronze mirrors found in many pagodas in the Kingdom of Wuyue and the Song dynasty were enshrined for a specific purpose. To explore this assumption and accurately understand the artifacts, this study focuses on the location and method of enshrinement. The number of bronze mirrors enshrined in pagodas increased during the Kingdom of Wuyue, with the mirrors expressing statues and inscriptions related to Buddhism rather than being simple offerings. This shows that the purpose of the bronze mirror changed. The influence of the Kingdom of Wuyue continued during the Song dynasty; however, the pattern of bronze mirror enshrinement changed due to the culture and social atmosphere of the time. The most common types of enshrined bronze mirrors were plain, and bronze mirrors from the Dang dynasty were also used consistently. Plain bronze mirrors were used more frequently in this period despite the lingering influence of the Kingdom of Wuyue because it was less laborious to engrave images and inscriptions such as the inscription of Buddha. Additionally, bronze mirrors were valued during this period because of the attention toward the imitation of the archaic bronze(仿古銅器) of the Song dynasty and the influence of the emperor. Moreover, it is believed that bronze mirrors were enshrined in pagodas as offerings as they were deemed valuable at the time. There was a change in the method of enshrining bronze mirrors in pagodas during the Kingdom of Wuyue and the Song dynasty. During this time, bronze mirrors that were positioned on the floor or in iron boxes were intentionally attached to walls or hung from the ceiling. This method was largely divided into two types: attaching to walls or the ceiling(嵌入鏡) and hanging from the ceiling(懸鏡). A typical example of hanging a bronze mirror from the ceiling can be seen in the Jingzhisa Temple Pagoda, and Teng County's Fushengsa Temple Pagoda contains an example of attaching a bronze mirror to the ceiling. The methods of hanging or attaching bronze mirrors to the ceiling were closely related to the methods employed in Chinese tombs. Song dynasty burial chambers had a high and wide structure, so to defend against evil spirits(辟邪用), bronze mirrors were used to protect the burial rooms. Bronze mirrors were, therefore, placed high to illuminate the burial room. This was achieved in the ways mentioned above. As underground chambers became wider and higher, mirrors also protected the important areas of the chambers and illuminated the interiors. Thus, it is believed that the methods of enshrining bronze mirrors in the pagodas during the Kingdom of Wuyue and the Song dynasty arose from the method of enshrining bronze mirrors in tombs at the time. Thereafter, pagodas, such as the Miaojuesa Temple Pagoda, in which the placement of a bronze mirror was actively considered from the design stage were constructed.

• 보존과학연구
• /
• s.21
• /
• pp.77-99
• /
• 2000

Tumuli located in Chodang-dong in Kangreung City are sitesexcavated by the Museum of Kangreung University in 1993.Ofthese sites, a gilt bronze crown and gilt bronze sword with ring pommel with a tri-leaf ornament were excavated from the B-16tumulus. Underneath the gilt bronze crown was the gilt bronzes word with ring pommel with tri-leaf ornament, and these artifacts were treated with Polyurethane foams on the spot followed by special measures for conservation. This manuscript describes measures for conservation andanalysis with regard to the gilt bronze crown, gilt bronze sword with ring pommel with tri-leaf ornament and gilt bronze beltornaments. Bronze on the gilt bronze crown was completely corroded, therefore it was consolidated together with soil in the back of the artifact with Paraloid B72 after cleaning. Polyurethanefoams bottom was finished by applying the mixture of Epoxy resinAW106 and HV935K with soil. On the sword with ring pommel, the wooden part of the hilt was coated with Paraloid B72 (in Xylene) and the blade was consolidated with Paraloid NAD-10 30% after desalting with Sodium sesquicarbonate method. The gilt bronzebelt ornaments were treated with 3% Benzotriazole, coated with Paraloid B72 and then joined by using Cyanlacrylate. Specimens for the gilt bronze crown and gilt bronze belt ornaments were produced and gilding layers were examined under a metallographic microscope. The gilt bronze crown and the gilt bronze belt ornament maintained relatively good gilding quality with uniform gilding layers. Analysis of wood for the sheath of the sword with ring pommel revealed it to be Juglans mandshurica. Further more, analysis of constituents for a blue colored grassbead from dissolution of Polyurethane foams found it to be from the $Na_2O$-CaO-$AI_2O_3$-$SiO_2$ family.

• Journal of the Korean institute of surface engineering
• /
• v.46 no.5
• /
• pp.197-207
• /
• 2013

In the midst of increasing importance of modern cultural assets, especially, most modern bronze objects are exposed to outdoor environment, and as the objects are corroded steadily due to environmental factors the objects lost their original colors on the surface. We performed artificial patinas on the bronze sample per each color of red, black and green and checked cuprite and tenorite which are detected from actual bronze corrosion by analyzing the components. In addition, we applied the existing corrosion removal methods of grinder and sand blaster on a similar sample of bronze mirror per injection pressure and performed comparative analysis on the result with Nd:YAG laser. As a result of Nd:YAG laser cleaning artificial patina from bronze samples, all of the patinas were removed by laser wavelength 1064 nm better than 532 nm. Upon applying to a similar sample of bronze mirror, the artificial patina could be selectively removed from substrates without surface damage when Nd:YAG laser was conducted other than the existing removal method, and so it showed the possibility of application.

• Journal of the Korean Chemical Society
• /
• v.62 no.2
• /
• pp.118-123
• /
• 2018

The hexagonal tungsten bronze $Cs_xWO_3$ nanoparticle was synthesized by a chemical coprecipitation method of ammonium tungstate and $Cs_2CO_3$ in acidic condition. This synthetic method for cesium tungsten bronze is reported for the first time as far as we know. The synthesized $Cs_xWO_3$ as precipitated showed a weak crystallinity of hexagonal unit cell with a crystallite size of about 4 nm without annealing. When the synthesized $Cs_xWO_3$ was annealed in $N_2$ atmosphere, the crystallinity and crystallite size systematically increased maintaining the typical hexagonal tungsten bronze structure as the annealing temperature increased. The analyzed Cs content in the bronze was about 0.3 vs W, which is very close to the theoretical maximum value, 1/3 in cesium tungsten bronze. According to XPS analysis, the reduced tungsten ions existed as both the forms of $W^{5+}$ and $W^{4+}$ and the contents systematically increased as the annealing temperature increased up to $800^{\circ}C$. The $Cs_xWO_3$ thin films on PET substrate were also prepared by a wet-coating method using the ball-milled solution of the annealed $Cs_xWO_3$ nanoparticles at various temperatures. The near-infrared shielding property of these thin films increased systematically as the annealing temperature increased up to $800^{\circ}C$ as expected with the increased contents of reduced tungsten ions.

• Conservation Science in Museum
• /
• v.26
• /
• pp.119-142
• /
• 2021

The gilt-bronze-and-silver shoes, excavated from the Tomb of King Muryeong, revealed many defective parts, which constantly raised in-depth re-investigation and reporting. In that point, scientific treatment and analysis were conducted to investigate the manufacturing techniques applied. The conservation treatment was carried out with an emphasis on the restoration of the original form and joining parts. As a result, the upper part of the right shoe and some part of the back heel were joined, confirming the joining method and the number of rivet used for instep bonding. From the component analysis, it is presumed that the outer plate was gilded with mercury amalgam on pure copper, and pure silver was used for the inner plate. The main pattern of the gilt-bronze-and-silver shoes includes designs of phoenix, lotus, and six-petal flower, while the lotus pattern is high in terms of ratio. Thus, youngnaksa(twisted gilt-bronze thread), geumdongsa(gilt-bronze thread), wondujeong (rivet), and samyeonjeong(quadrangular cleats) were used for bonding each plate. Twisted gilt-bronze thread was used to join the inner and outer plates, while the center and rear of the inner plate were combined with only gilt-bronze threads. From the fact, it is presumed that the joining method was different whether the function was decoration or just bonding. Regarding the manufacturing process, traces of burnishing were confirmed on the outer surface of the gilt-bronze and silver shoes, but no burnishing traces were identified on the inner surface of the silver plate, which is likely to prove more importance put on the finishing of the outer plates rather than that of the inner.

• 한국전기화학회:학술대회논문집
• /
• 2001.04a
• /
• pp.38-38
• /
• 2001

• Conservation Science in Museum
• /
• v.20
• /
• pp.1-12
• /
• 2018

In February 1986, a high-school student reported the discovery of fragments of gilt-bronze burial goods on a mountainside behind a village in Ipjeom-ri, Ungpo-myeon in Iksan. The National Research Institute of Cultural Heritage immediately undertook an excavation. Unfortunately, gilt-bronze relics including a band and vertical decorations for a crown, a hat, and shoes had already been collected from Ipjeom-ri Tomb 1 by the student who found them before they could be properly excavated. Also, the interior of the stone chamber of the tomb had been severely disturbed by the time of excavation, making it difficult to identify the precise original locations of the relics within the tomb and hindering the reassembly of the fragments of the gilt-bronze crown. After conservation treatment, the gilt-bronze hat, shoes, and other relics were restored to their original forms and researchers were able to identify incised designs of a three-legged bonghwang(鳳凰), fish scales, lotus flowers, and other motifs. This study presents the major features of the fragments of gilt-bronze relics from Ipjeom-ri Tomb 1 and the methods of their production in order to provide basic material for their restoration and allow the eventual restoration of the giltbronze crown to its original condition.

• Advances in nano research
• /
• v.12 no.6
• /
• pp.583-592
• /
• 2022

In this paper, a pulsed picosecond laser dressing method for bronze-bonded diamond wheel is studied systematically and comprehensively. The picosecond laser pulse ablation experiment is carried out, and the ablation thresholds of bronze-bonded and diamond abrasive particle are measured respectively. The results indicate that the single-pulse ablation thresholds of bronze-bonded are 0.89J/cm², 0.24J/cm² during strong/weak ablation stages. And the multi-pulse ablation thresholds of diamond abrasive particle are 1.69J/cm², 0.49J/cm² during strong/weak ablation stages. Obviously, diamond grains have less thermal damage during the process of gentle ablation. The diamond grains of the grinding wheel surface are graphitized during laser dressing. The bronze-bonded is relatively smooth and organizational stability, and the diamond grits have suitable prominent height, which are beneficial to maintain the good grinding performance of dressed bronze-bonded diamond grinding wheels.