High-tin Bronze Research Articles

Analysis on the Ancient Bronze Cooking Outils Excavated from Historic Site of Anti-Mongolian Struggle in Hangpaduri, Jeju

The microstructure of ancient bronze cooking outil excavated in historic site of anti-Mongolian struggle in Hangpaduri was analyzed to confirm various manufacturing techniques. Bronze spoon and bronze ladles were made by alloying only copper and tin, and the alloy ratio included approximately 22% tin in the copper composition of the forged high tin bronze. The manufacturing process of forged high tin bronze technology, which commonly involves high-temperature forging and final finishing with quenching, was performed. In addition, the sulfide elongated in the longitudinal direction shows that the copper material supplied to the metal may be copper ore containing sulfur such as chalcopyrite and chalcocite. The three bronzewares were made using a binary alloy of copper-tin and a ternary alloy of copper-tin-lead, respectively. Manufacturing techniques using a binary alloy of copper-tin are divided into a forged high tin bronze technique using a hammering and quenching process and a manufacturing technique system of quenching after casting into a shape. Bronze bowl made using a ternary alloy of copper-tin-lead contain 11 wt% tin and 9 wt% lead in the main metal of copper. The lead contained in large quantities is formed in an uneven size within the microstructure, and shows the characteristic of sulfide being distributed around the lead. In addition, there are no traces of additional processing or heat treatment such as quenching. Therefore, it can be seen that the work process was completed by casting the shape. The results of the microstructure analysis show various manufacturing technology systems applied to the bronze cooking outils from historic site of anti-Mongolian struggle in Hangpaduri, Jeju. In particular, through comparison with bronze artifacts utensils excavated from other regions of the Sambyeolcho’s historic site, the possibility of bronze being introduced due to the migration of the Sambyeolcho was confirmed.

Study on Softening Resistance of Cu-Sn-Fe-P alloy for Advanced Electrical Connectors

The effect of adding iron element in tin bronze on the microstructure and properties of Cu-Sn-Fe-P alloy is studied by means of phase diagram calculation and microstructure observation. The work hardening curve of Cu-Sn-Fe-P alloy is plotted by cold deformation of the alloy with different reduction rates. The test and microstructure observation are conducted for tensile strength and ductility of the alloy sample annealed at different temperatures, so as to determine the recrystallization temperature of the alloy. The results show that the addition of iron element plays a significant role in grain refinement and improves the subsequent working performance. After the cold rolling deformation, an obvious work hardening effect is imposed on the alloy. With the increase of the deformation, the alloy presents a trend of increasing first and then becoming stable in the tensile strength, while a reverse trend in ductility. Cu-Sn-Fe-P alloy has a softening resistance equivalent to that of QSn6.5-0.1 high-tin bronze, both of which will be softened at 400ºC; therefore, Cu-Sn-Fe-P alloy can replace QSn6.5-0.1 alloy at high temperature.The present study proposes how to maintain the original properties of the tin-phosphorous bronze alloy while reducing the content of the tin, and achieve the more effective industrialized production.

Tin isotopes reveal changing patterns of tin trade, connectivity and consumption from Anatolia and Central Asia at Kültepe

Until recently, what was known about the trade of tin in the ancient Near East was based in large part on information derived from the extensive commercial archives found at the archaeological site of Kültepe (ancient Kaneš) in Turkey dating to the Middle Bronze Age (MBA) c. 1900-1750 BC. These archives were produced by an expatriate community of traders native to the city of Assur in modern-day Iraq and document an extensive shipping of tin ingots from unnamed sources east of their hometown. Tin was carried by donkeys through northern Syria and across the Taurus Mountains to Anatolia where it was sold for silver.This paper presents the first set of tin isotope analyses of bronze objects from Kültepe to test the image provided by these ancient archives, finding that all artifacts dated to the main period of Assyrian trade excavated in the residential areas of the site indeed have high tin content and high values of δ124Sn (0.77–1.74‰) relative to the NIST 3161a standard. Such high values currently compare best with ores from Central Asia. The isotopic analysis of artifacts from the Assyrian Trading Colony Period of Kültepe is therefore consistent with the textual evidence.However, Early Bronze Age samples recovered at the site are instead characterized by lower ranges that extend to neutral δ124Sn values (0.02–1.31‰). Likewise, one artifact coming from Mound Level 7 (c. 1830-1700) at the center of the site where public buildings were concentrated, and one object dated to the Hellenistic Period (Mound Level 2), when the site saw a resurgence in political importance, likewise have lower δ124Sn compositions of 0.11 and 0.31‰, respectively. Both samples also have low to moderate tin content.The Early Bronze Age artifacts form a linear array between artifacts from low δ124Sn-low Sn wt% to high δ124Sn-high Sn wt% that suggests a mixing of two compositional groups – not simply the mixing of two isotopically distinct reservoirs of tin, but also distinct in the amount of tin present in the alloy. This would be consistent with the recycling of low tin bronze objects with local tin, together with high tin bronzes containing tin from Central Asia. The two samples from Mound Levels 7 and 2 suggest that although Central Asian tin was predominant in the MBA, Anatolian tin may have continued to be used in a separate bronze production system that remained active at shifting varying of intensity throughout antiquity.

Manufacturing Techniques of Ancient Forged High-tin Bronze Wares from Archaeological Sites in Bagan, Myanmar

Bronze wares made with forged high-tin bronze technology were first produced in the Persian region of the Orient, gradually brought to India and then to China and the Korean Peninsula. By scientifically analyzing bronze artifacts of Myanmar, which is located halfway between Persia and Korea, it is possible to confirm the trade and the propagation route of technology at the time. This study scientifically analyzed bronze artifacts excavated from the Bagan ruins in Myanmar to identify the manufacturing technology. Forged high-tin bronze wares in Bagan Dynasty are with alloy compositions Cu-Sn. Composed of Cu-Sn only were manufactured by alloying Cu with Sn in a ratio of 76 wt% and 24 wt%, which is a relatively high tin content. High-tin bronze wares composed of Cu-Sn were manufactured with the bronze material of an alloy of Cu and a large amount of Sn by hot working (forging) and finished by quenching. The microstructure indicates temperatures at which the quenching was performed and various microstructures that occur in different temperature ranges are observed such as β (M), γ phase, δ phase as well as primary crystals, α phase. The presence of different microstrucures suggests multiple high-tin bronze wares were quenched at a wide range of temperatures. The non-metallic inclusions of the bronze wares contain sulfur, which indicates with high possibility that the copper provided as the raw material was extracted from copper ores containing sulfur.

The Metallic Sounds: A Microanalytical Study on the Production of Armenian Church Bells from Iran.

There are a considerable number of church bells in museums, examples include the museum of the Vank Cathedral and the Treasury of Armenian Music in New Julfa, both located in Isfahan, Iran. These objects were collected from different Armenian churches and cathedrals in Iran and were dated to ca. 400-100 years ago. Due to the long history of Armenians in Iran and their important role in its cultural and architectural development, study of the production technologies they utilized is a subject of interest for art historians and scientists. Three metallic bells from the Treasury of Armenian Music in New Julfa were selected for a multianalytical study to investigate their manufacturing methods, using micro-XRF, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), and metallography techniques. The results showed that the bells were produced with a binary tin bronze alloy with 13 to 20 wt% of tin, classified as either low-tin or high-tin bronze, depending on the concentration. The analysis showed a two-phase cast microstructure consisting of the α solid solution with significant amounts of interdendritic α + δ eutectoid. The results also indicate that the bells are cast first, but some evidence of complementary thermomechanical operations is visible in their microstructure.

Mechanism of incipient annular corrosion of high-tin bronze in simulated soil solution

ABSTRACT The mechanism of Cu–Sn–Pb bronze (18.2 wt-% Sn) in a simulated soil solution was examined using optical microscopy, scanning electron microscopy, scanning Kelvin probe, X-ray photoelectron spectroscopy, X-ray diffraction and electrochemical techniques. The findings demonstrated that the α-phase possessed a more negative corrosion potential, and the central annular position was more active owing to the difference in the solid-solution tin content during casting. Cl− was not directly involved in the production of corrosive products in the early stage of corrosion, but it damaged the copper oxide layer and promoted the loss of copper ions. Subsequently, the tin oxide was gradually produced on the surface, and the selective copper dissolution led to abundant tin compounds on the surface.

Mechanism of Incipient Annular Corrosion of High-Tin Bronze in Simulated Soil

Mechanism of Incipient Annular Corrosion of High-Tin Bronze in Simulated Soil

Micro-structural and micro-chemical investigation of Samnite high-tin bronze cuirass discs: ancient metallurgy in central Italy

In the present study, micro-structural and micro-chemical investigation of archaeological bronze artefacts provided new insight about the metallurgical manufacture of defensive weapons by the Samnite’s metalsmiths in central Italy from the archaic necropolis of Barrea (AQ) and Torrebruna (CH). In particular, the metallurgical features, the chemical composition and the manufacturing process of Cu-based high-tin alloys used to produce cuirass discs were investigated. These artifacts were used to protect the warrior’s heart (i.e. the kardiophylaches) but were also and more importantly a distinctive sign of rank and role of warriors of the archaic age (VI BC). The Samnite cuirass discs are multi-material artifacts made of a decorated bronze central part with a complex metallurgical structure, due to the presence of different Cu-Sn phases, and a surrounding iron cladding to support the disk. These discs were studied by different surface and bulk techniques, namely Optical Microscopy (OM), Field Emission Scanning Electron Microscopy coupled with energy dispersive X-ray microanalysis (FE-SEM-EDS), X-ray Diffraction (XRD) and Infrared Spectroscopy (FTIR). The combined use of these techniques proved the high technological level of the Samnite metallurgists. In fact, their particular composition, having an uncommon high content of tin, made their manufacturing process difficult because of the intrinsic brittleness of the alloy. This work disclose the ability of Samnites people to successfully manipulate fragile high tin bronze alloys by inducing temporary phase changes and, thus, facilitating the mechanical shaping of the artifact.

The complex atmospheric corrosion of α/δ bronze bells in a marine environment

• Long term corrosion of a high-tin bronze bell in a steeple under marine atmosphere. • A corroded high-tin α/δ alloy Cu-Sn-Pb: comparaison with ancient buried artefacts. • Complex alteration due to environment, shocks and vibrations of bells. • Particular pitting corrosion of α/δ alloy. • Hypothesis of a micro-infiltrating alteration scenario of the α/δ bronze bell. α/δ bronze bells are heritage materials subject to corrosion. The alteration of a high-tin bronze bell casted in the 1930s and exposed to a marine environment in a steeple was studied. The ternary bronze (Cu-Sn-Pb) alloy displays inclusions and a porosity due to micro-shrinkages and poor gas evacuation. This altered bronze is characterized to (1) assess the influence of the manufacturing techniques and (2) hypothesize a micro-infiltration scenario of its alteration. After exposure to the atmosphere, a transformed superficial medium overlaying layers of atacamite-paratacamite-cassiterite appears. Under them, the corrosion of the α dendritic structure and α/δ eutectoid characteristic of bronze bell is evidenced. The α pitting has a pronounced multilayered structure of cassiterite and cuprite-copper chloride, whereas the δ corrosion is composed of cassiterite and traces of cuprite. To understand better the lead impact on corrosion process, samples of the alloy were exposed in the laboratory to a synthetic marine solution. The long-term corrosion behavior of the studied bell shows some similarities to those of other high tin bronze artefacts. The hypothesis of a corrosion scenario emphasizes the importance of the bells manufacturing techniques, α/δ structure of the ternary Cu-Sn-Pb alloy, and infiltrating networks of environmental fluids.

Lead Isotopic Characteristics and Metal Sources for the Jewelry in the Medieval Rural Settlements from the Suzdal Region (Kievan Rus’)

The article considers the results of the study of lead isotope composition of 38 non-ferrous artifacts discovered at medieval rural sites of the Suzdal Region (Kievan Rus’). The copper-alloy, silver and pewter artifacts were compared with reference data from geographically and temporally diverse medieval artifacts and ore deposits and revealed differing source regions and supply networks within and between metal types. The identification in some cases was difficult due to the conformity of the lead isotopic composition of deposits of some regions. The copper-alloys, represented mostly by crosses made of high-tin bronze, show close isotopic parallels to contemporary copper alloys from Southern Scandinavia, Westphalia and Lower Saxony. Since the copper alloys contain significant quantities of lead, this lead may have entered the metal by alloying with lead-tin alloys, by smelting mixed copper-lead ore, or through haphazard alloying with lead. The lead isotope ratios for nearly all copper alloys are consistent with deposits in Cornwall and Devon and remobilized ore from the Rhenish Massif. For silver and lead-tin alloy objects, lead isotope analyses point to wide ranging sources. Most silver objects are consistent with mid-to-late 10th century silver stocks circulating in the Baltic area and 10th century Volga-Bulgar silver dirham imitations probably representing mixtures of 9th-10th century Islamic silver. The silver shows a heavy reliance on 10th century mixed stocks and there are little indications of Central and Western European silver, which was common in the 11th century Baltic region. The pewter and lead, however, indicate other sources. Lead isotope ratios are consistent with sources connected to Mediterranean and Baltic networks, some being consistent with sources in England, but it is possible that the lead found in some pewter objects could come from the Olkusz lead district in southern Poland.

Aesthetic of Brightness in Han Mirror Inscriptions


 
 
 This article analyzes inscriptions cast on bronze mirrors of the Han dynasty (202 BCE–220 CE) to trace how the material property of brightness became emphatically aestheticized through an expressive rhetoric of radiance and brilliance, illumination and reflection. It argues that specular brightness as a defining feature of Han mirrors was exploited by artisans to attract potential buyers . In contrast to erudite philosophers who exclusively used the logograph ming 明 to modify the literary mirror in classical texts, artisans promoted their products by featuring terms such as guang 光, zhao 昭, hui 輝, yao 耀, qing 清, and jiao 皎 in rhythmic proses of various lengths . Examining how artisans advertised their high-tin bronzes as embodiments of solar and lunar light, the study shows that specular brilliance was linked to a range of cosmetic, moral, and religious powers, from illuminating the individual and the physical world to revealing the invisible world, whether of human emotions or demons . The article further argues that the inscribed verses, while often formulaic and clichéd, were neither mere decorations nor generic blessings . In fact, they meaningfully structured and communicated a particular aesthetic appreciation shared by both Han artisans and users . This well-developed semantic fascination with specular brightness thus marks these metal discs as a distinctive genre of the decorative arts in early imperial China .
 
 

Effect of deep cryogenic treatment on C93700 bearing bush material used in submersible pumps

Bearing bush is an essential part of a rotating machine. It is inserted in a housing to support the motor shaft of a submersible pump with a radial clearance of 40 μm. This plain bearing is made of high lead tin Bronze, C93700. In the working condition the submersible pump stacked with series of impellers is assumed to be an overhanging structure as the fluid flow through the impellers is not uniform in the beginning. This imbalance leads to the misalignment between pump and motor shafts resulting in the contact of bearing bush with motor shaft, as the shaft material AISI 420 stainless steel is harder than the bearing material, wear out of latter is inevitable. Due to the continuous running of motor in this condition for long hours, the shaft comes in contact with the stator and the stator coils begin to burn implying the breakdown of pump set within 6–12 months of installation. This paper aims to improve the hardness and wear resistance of C93700 bronze through deep cryogenic treatment. The test samples of the material were treated with liquid Nitrogen at −196℃ temperature and tested for tensile strength, hardness and wear resistance. Microstructure of the samples have been examined using SEM and chemical analysis was done through EDS.

Монетные сплавы Херсонеса Таврического периода независимости

This paper presents the results of X-ray fluorescence analysis of the composition of alloys of the two largest collections of coins of ancient Chersonese residing in the State Historical and Archaeological Museum Preserve of Tauric Chersonese and the Yevpatoria Regional Museum. In total, about a thousand coins studied, which, together with the 400 coins previously examined from the State Hermitage Museum, constitutes a solid basis for conclusions. The given paper analyses the data obtained for coins of Chersonese in the Period of Independence, that is from the emergence of local coinage in the early fourth century BC to the wars of Diophantos in the late second century BC. For the first time it has been determined that big dichalkoi were minted from a special coin alloy, two-component high-tin bronze, in the period of economic prosperity of Chersonese in the second half of the fourth and third centuries BC. These coins served as the financial basis for important transformations in the near and distant chora: the land division system of vineyards and territorial expansion of Chersonese into the north-western Taurica. Only in the third century BC, in the period of an unprecedented consolidation of land properties and the transformation of the wine production into a commodity industry, the minting of large silver coins of full metal value began probably for big financial deals and payments in international trade. The crisis in the minting of Chersonese in the late second century BC touched silver drachmae, the overwhelming majority of which were minted from a low-grade silver alloy with the copper comprising more than a third of the composition. Thus, full-weight coins turned to conditional money.

Characterisation of Archaeological High-tin Bronze Corrosion Structures

ABSTRACT Since ancient times, the use of high-tin bronze alloys (>17 wt.%) has been mainly limited to the production of specific objects such as mirrors and bells. High-tin bronzes can show distinctive colour reflection, as well as mechanical properties and corrosion resistance that clearly distinguish them from the classical bronze composition (with 8–12 wt.% tin). In the present study samples of archaeological high-tin bronze bells were studied by optical microscopy, SEM-EDX, and Raman imaging with the aim of characterising their microstructural long-term corrosion patterns. Results show the presence of high quantities of δ phase, when compared to the classical bronze composition, which makes some corrosion structures more visible in these alloys. The corrosion morphologies show selective corrosion of different metal phases along depth of corrosion, which were attributed to different oxygen potentials. This study proposes a classification of four types of corrosion structures occurring in two-phase bronzes as a consequence of aeration conditions during burial time and aeration within the corrosion structure.

Effect of High-tin Bronze Composition on Physical, Mechanical, and Acoustic Properties of Gamelan Materials

Effect of High-tin Bronze Composition on Physical, Mechanical, and Acoustic Properties of Gamelan Materials

Preparation of High-tin Bronze Corrosion-resistant Coating by Potentiostatic Pulse Electrodeposition

Preparation of High-tin Bronze Corrosion-resistant Coating by Potentiostatic Pulse Electrodeposition

Manufacturing Techniques and Alloying Compositions of Metal Decorative Artifacts in 18th Century, Myanmar

Konbaung Dynasty was the last unified dynasty that ruled Myanmar from 18th to 19th century. During this time Buddhist art flourished in Myanmar due to the interest of the rulers toward their traditional culture. Metal decorative artifacts in the 18th century are classified into structures and Buddha statues. They are further subdivided into gilt-bronze and bronze objects, depending on their material component. Three-dimensional gilt-bronze decorative artifacts were cast with a brass alloy of Cu-Zn-Sn-Pb and their surfaces were gilded with extremely thin gold leaves (less than 1 μm in thickness). The gilded layer approximately comprised 10 wt% silver in addition to the main element, gold. The lack of Hg in the gilded layer, indicated that the amalgam gilding technique was not applied. The analysis results indicated that the lacquered gilding technique was applied to the objects. Bronze decorative artifacts without gilding were cast with materials containing Cu-Sn-Pb. The bronze pavilions and bronze Buddha staues were crafted using the same alloy of high-tin bronze, which approximately contained 20 wt% Sn. No heat treatment was applied to reduce the brittleness of the objects after they were cast with a large amount of Sn. The most significant difference between the gilt-bronze and bronze decorative artifacts lie in their elemental compositions. The gilt-bronze decorative artifacts with their gilded surface were manufactured using brass containing zinc, while the unplated bronze decorative artifacts were composed of bronze containing tin. Artifacts of the same type and size are classified differently depending on the materials utilized in the surface treatment such as gilding.

Inlaid materials and techniques of an ancient Chinese bronze mirror

A bronze mirror was unearthed at Xi’an, China, the capital of the Sui dynasty (581–618 AD). The utilized inlay technique is unique and no similar mirrors have been found in China. This study analyzed the structure and composition of the inlays via digital microscopy, metallography, scanning electron microscopy and energy disperse spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, X-ray fluorescence and Raman spectroscopy. The results identified the mirror as a casted high-tin bronze, and each inlaid block included four layers: a mineral base layer (clay and raw lacquer), a gold leaf layer (made of native gold), a pigment layer (malachite and minium) and a glass layer (high-lead glass and sodium-calcium glass). The soda-lime glass is a plant ash glass that likely originated from the Sassanid area. The utilized techniques involved the two crafts of gold pasting (Tie Jin) and pigment filling (Tian Cai). Pigment filling was rarely used in bronze works of the Sui dynasty. This study provides new information on the ancient Chinese bronze mirror-making technology.

Forging Technology of High-Tin Bronzes in Ancient Bengal

Forging Technology of High-Tin Bronzes in Ancient Bengal

A Scientific Study of Eastern Zhou Bronze Weapons with Tin-Rich Surface Decoration

In this paper we examined three bronze weapons with tin-rich surface decoration from the Eastern Zhou period: a sword (1966,0222.1) with a trellis pattern, a spearhead (1947,0712.426) with a hexagonal star pattern in the British Museum collections, and a sword (GT698) with a trellis pattern from a private collection. These weapons may have come from south eastern China, a region renowned for its weaponry production in the Eastern Zhou period, as both their styles and decorations are comparable to the sword of the Yue King Goujian and the spearhead of Wu King Fuchai, two of the most typical objects of this type. The manufacturing and surface tin-rich decoration techniques were investigated using microscopy, X-ray CT imaging, X-ray fluorescence spectrometry, scanning electron microscopy equipped with energy dispersive X-ray spectroscopy, and X-ray diffraction. The results showed that all the objects were made of high tin bronzes. The swords were made by casting a grip around the pre-cast blade and the pommel. The spearhead was an integral casting. The trellis pattern on the swords was probably produced by heating up a tin-rich paste applied to the surface and the thin hexagonal star decoration pattern on the spearhead was probably produced by brush painting with a mercury-tin amalgam followed by heating.