METHOD OF MANUFACTURING PRECIOUS METAL PRODUCTS THROUGH ROLLING AND IMPRESSING TECHNIQUES, AND PRECIOUS METAL PRODUCTS MANUFACTURED THEREBY

摘要

The present invention relates to a method of manufacturing precious metal products through rolling and impressing techniques, and precious metal products manufactured thereby. More specifically, the method of the present invention can manufacture precious metal accessories such as gold turtles, gold pigs, keys of good luck, and Hahoe masks, and cameo portions in cameo coin products and cameo metal products, through rolling and impressing techniques using a prepared ingot, thereby reducing the manufacturing cost while increasing the manufacturing speed compared to the existing casting technique. Further, the method of the present invention can be applied to manufacturing of cameo coin products and cameo medal products, other than target precious metal accessories such as gold turtles, gold pigs, keys of good luck, and Hahoe masks, and therefore is appropriate for manufacturing various precious metal products. Furthermore, according to the method of the present invention, in the annealing process of precious metal products, without using expensive annealing devices, annealing effects similar to when using such expensive annealing devices can be achieved through exposure to the fire of an oxygen torch for 2-3 seconds. In the conventional washing process of precious metal products using chemicals such as lubricants and hydrogen peroxide, a post-treatment operation was needed after removing foreign materials, to remove the chemicals, thus increasing the manufacturing cost and causing environmental problems due to oils and chemicals. Unlike the conventional process, the method of the present invention uses water and surfactants to wash the precious metal products, thereby reducing the manufacturing cost and alleviating the environmental problems. According to the method of the present invention, when manufacturing precious metal products, an outer edge of a sheet material that is formed by impressing a precious metal sheet inserted between an upper plate mold and a lower plate mold, is cut through an outer edge cutting mold, and thus the precious metal products can be simply manufactured with finished outer edges.;COPYRIGHT KIPO 2018