제조공정에 따른 고려시대 청동용기의 미세조직과 기계적 특성 변화

Abstract

Bronze vessels are manufactured using casting and forging techniques, and variousmicrostructures can be observed depending on the manufacturing process. In this study, we confirmedmechanical properties and microstructural evolution in the manufacturing process by observing themicrostructures and composition analysis of 18 bronze vessels in the Goryeo Dynasty excavated fromhistorical sites. The results show that 13 of the bronze vessels were manufactured using a Cu-Sn alloy witha Sn content of 20 to 24 wt%. The  phase and (M) phase were observed, indicating that hot forging andquenching treatment were performed after casting. 3 bronze vessels were produced from a Cu-Sn-Pb alloy,and considering that the  phase and +δ phase were observed, it could be seen that the process wascompleted by slow cooling after casting. The correlation between the type of bronze vessel and themanufacturing process has not been confirmed, except of ewer. It was confirmed that various microstructureswere created depending on the manufacturing process and that the mechanical properties also changed. Bronze vessels composed of the  phase and +δ phase due to the casting process had lower Vickers hardnessvalues compared to bronze vessels that showed the quenched (M) or  phase. Electron backscatter diffraction(EBSD) phase analysis and kernel average misorientation (KAM) were performed using six bronze vesselscomposed of  and (M) phases. The results showed that the factors affecting hardness were the ratio of the(M) phase and the KAM value. However, it could not be confirmed to what extent the ratio of the (M) phaseand KAM value affected the improvement in mechanical properties.