• Journal of Conservation Science
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• v.33 no.6
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• pp.519-532
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• 2017

Studies on ancient ironmaking technologies are primarily based on archaeological surveys and scientific analysis data, and technological systems are examined by comparing the results of restorative experiments. In this study, to examine the ancient iron production technologies such as smelting and smithing in the Jungwon area, a restoration experiment was conducted based on archaeological data, and the iron and slag, etc. produced in the experiment were analyzed. Further, the changes in physicochemical properties due to the smelting of the raw material, specifically, iron ore were determined, and the smithing process, which involves fabrication of ironwares, was analyzed along with the characteristics of each step. In the case of smelting, increasing recovery rates and production of high-quality primary iron material were important for the following processes. For the iron bars produced through the smithing process, it was found that quality improvements made by reducing physical defects such as inclusions or gas holes were more important than the composition of the iron itself. The study also yielded comparative study data for various byproducts, such as smithing slag, which could be utilized in other ironmaking technology studies.

• Journal of Conservation Science
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• v.32 no.2
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• pp.189-202
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• 2016

To figure out the material characteristics about slag and raw materials which are founded in iron product sites in Seosan area, we used XRF, EDS to analysis chemical compositions. Also we observe the microstructure by microscope and SEM. To identify the mineral component, XRD analysis was used and to assume the provenance of the raw material, lead isotope ratio analysis was used. From the results, we figure out that slags are non-ferrous created when metal was refined. Also, main tissue of slags were Fayalite, Galena, Magnetite, and raw materials were identified as mineral of Galena, Anglesite, Pyrite etc. From the result about lead isotope ratio analysis, we found out most samples are classified as the Western Gyeonggi massif in South Korea. Especially three of raw materials and slag samples which collected in the Seosan Doseongri was presumed to be the provenance. We figure out that slags we analyzed were made in non-ferrous metal smelting process and especially that were more likely to smelt from Seosan Doseongri. If various slags in this area are analysed by someone, It will contribute understanding non-ferrous metal refining process as well as metal refining which are composed.

• Bulletin of the Korean Chemical Society
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• v.23 no.11
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• pp.1531-1540
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• 2002

With the invention of the inlaying technique for celadon in the latter half of the 12th century, the Koryo potters reached a new height of artistic and scientific achievement in ceramics chemical technology. Inlaid celadon shards, collected in 1991 during the surface investigation of Kangjin kilns found on the southwestern shore of South Korea, were imbedded in epoxy resin and polished for cross-section examination. Backscattered electron images were taken with an electron microprobe equipped with an energy dispersive spectrometer. The spectrometer was also used to determine the composition of micro-areas. Porcelain stone, weathered rock of quartz, mica, and feldspar composition were found to be the raw material for the body and important components in the glaze and white inlay. The close similarity between glaze and black inlay in the microstructure suggests that the glaze material was modified by adding clay with high iron content, such as biotite, for use as black inlay. The deep soft translucent quality of celadon glaze is brought about by its microstructure of bubbles, remnant and devitrified minerals, and the schlieren effect.

• Journal of the Korean Solar Energy Society
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• v.28 no.5
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• pp.8-13
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• 2008

In this study, we analyze the electrical optical characteristics of transparent glass for photovoltaic and glass-glass module application. The elemental facts from raw glass to laminated glass with solar cells are analyzed using UV spectrophotometer and spectroradiometer. From the data of transmittance and reflectance, the optimum PV module processing condition and selection of material for fabrication should be considered deeply for obtaining high module efficiency. Also we introduce two glasses which has 2%$\sim$4% higher transmittance using coating technology with anti-reflection material. From this experiment, we try to give some basic information for PV module manufacturing industry. The detail description is specified as the following paper.

• Journal of Conservation Science
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• v.30 no.4
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• pp.335-343
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• 2014

This study classified the result of non-metallic inclusion analysis and result of microstructure investigation on the ironware excavated in the Baekje region into Han River, Geum River, and Yeongsan River to estimate the iron making temperature and study the characteristics of regional and temporal characteristics of the heat treatment technology and steel making technology. Regardless of era, bloom iron and sponge iron are judged to be the major method for making as a directreduction process in all three regions. The result of the reinterpretation of the non-metallic inclusion by the oxide ternary constitutional diagram suggest that the temperature inside of the furnace is estimated to be between $1,100{\sim}1,300^{\circ}C$ while making the steel. The magnetic iron ores are the major raw material of steel ore and irons with high $TiO_2$ are estimated to use iron sands. Ironware with $CaO/SiO_2$ rate higher than 0.4% are considered to have artificially added the flux of calcareous materials. It was found that the iron making method is the solid caburizing-steel which caburizes low-carbon steels by the CO gas and $CO_2$ gas created when heating the forging furnace with charcoal. Also, the ironware manufacturers in the Baekje during 3rd century recognized the heat treatment technology as they performed carburizing process and quenching to intentionally increase the strength of necessary parts.

• Resources Recycling
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• v.29 no.1
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• pp.3-16
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• 2020

This work provides an overview of the steel production process, pretreatment and tramp elements of scraps and recycling technology of dust generated from steelmaking process. Steel is the most common metal used by mankind, with the world production of crude steel in 2018 exceeding 1.8 billion tonnes. Recycling of ferrous scraps reduces CO₂ emissions by about 42 % and saves about 60 % of energy, compared to production steel from iron ore. Steel scraps are usually recycled to both an electric arc furnace (EAF), scrap-based steelmaking and the basic oxygen furnace (BOF), in ore-based steelmaking. EAF steelmaking, which uses iron scrap as a main raw material, is changing to an energy-saving type with a device for preheating scrap. Dust generated from the steelmaking process is recycled in various ways in the steel mill to recover iron and zinc.

• Journal of architectural history
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• v.31 no.4
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• pp.7-16
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• 2022

Since the beginning of the second Sino-Japanese war in 1937, the entire Korean Peninsula has entered a full-fledged wartime system. Japan enacted laws that strongly regulate the distribution of various resources for war, and the same was implemented in Joseon. In particular, as iron, copper, lead, tin, and aluminum were mobilized as raw materials for military supplies such as weapons, private distribution decreased significantly, which had a great impact on the construction industry. As the use of metal such as steel as building materials requires permission from the provincial governor, it has become difficult to supply and demand except for some military facilities. In addition, the Japanese Ministry of Commerce and Industry encouraged research and development and manufacturing to promote the so-called "substitute goods industry" to make up for the shortage of supplies. Products with improved performance through chemical treatment by injecting only a small amount of the same raw material than before or using alternative raw materials have been developed. It was intended to overcome the limitations of lack of raw materials through the chemical industry. In terms of building materials, various substitutes were produced due to the incorporation of petrochemicals and the use of synthetic resins. This trend continued even after the end of the war and served as one of the backgrounds for R&D and production of new materials without returning to the "substitute goods."

• Korean Journal of Materials Research
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• v.33 no.4
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• pp.151-158
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• 2023

In this study, a new type of composite material combined with carbonyl iron, a relatively strong ferromagnetic material, was prepared to overcome the current application limitations of Prussian blue, which is effective in removing radioactive cesium. The surface of the prepared composite was analyzed using SEM and XRD, and it was confirmed that nano-sized Prussian Blue was synthesized on the particle surface. In order to evaluate the cesium removal ability, 0.2 g of the composite prepared for raw cesium aquatic solution at a concentration of 5 ㎍ was added and reacted, resulting in a cesium removal rate of 99.5 %. The complex follows Langmuir's adsorption model and has a maximum adsorption amount (q_e) of 79.3 mg/g. The Central Composite Design (CCD) of the Response Surface Method (RSM) was used to derive the optimal application conditions of the prepared composite. The optimal application conditions achieved using Response optimization appeared at a stirring speed of pH 7, 17.6 RPM. The composite manufactured through this research is a material that overcomes the Prussian Blue limit in powder form and is considered to be excellent economically and environmentally when applied to a cesium removal site.

• Korean Journal of Construction Engineering and Management
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• v.9 no.1
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• pp.187-198
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• 2008

There are usually plenty of material inventories in a construction site. More inventories can meet unexpected demands, and also they may have an economical advantage by avoiding a probable escalation of raw material costs. On the other hand, these inventories also cause negative aspects to increase costs for storing redundant inventory as well as decreasing construction productivity. Therefore, a proper method of deciding an optimal level of material inventories while considering dynamic variations of resources under uncertainty is very crucial for the economical efficiency of construction projects. This research presents a stochastic modelling method for construction operations, particularly targeting a work process involving on-site fabrication of raw materials like iron-rebar process (delivery, cut and assembly, and placement). To develop the model, we apply the concept of factory physics to depict the overall components of a system. Then, an optimal inventory management model is devised to support purchase decisions where users can make timely actions on how much to order and when to buy raw materials. Also, optimal time lag, which minimizes the storage time for pre-assembled materials, is obtained. To verify this method, a real case is applied to elicit an optimal amount of inventory and time lag. It is found that average values as well as variability of inventory level decreased significantly so as to minimize economic costs related to inventory management under uncertain project condition.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.1
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• pp.107-113
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• 1992

This paper is the part of fundamental study considering whether the unprocessed water cooled blastfurnace slag, by-product of iron works, can be useful for some fine aggregate of mortar and concrete. The acquired results in this study show that the qualities of the water cooled blastfurnace slag produced in the state of raw material in the country in not good for using as a fine aggregate of mortar and concrete. To be used as a fine aggregate of concrete the qualities need to be improved in the process of manufacture.