In the light of the bronzes so far unearthed from the Yin Ruins and their casting technology known through researches,the present paper studies the bottom mold of large-sized bronze vessels unearthed from Xiaomintun o...In the light of the bronzes so far unearthed from the Yin Ruins and their casting technology known through researches,the present paper studies the bottom mold of large-sized bronze vessels unearthed from Xiaomintun on the Yin Ruins in the excavation of 2003 to 2004,and affirms its casts to have been large-sized bronze pan basins.Taking into account related historical records and oracle-bone inscriptions,the author concludes that Shang and Zhou bronze pan were all wash-vessels and a little differed from each other in use.Moreover,during the Shang-Zhou period,there was intricate washing ritual,including not only ceremonious actions of face,hair and hand washing,but also those of all body bathing in large-sized pan in the case of grand sacrificial activities.展开更多
ZL205 A alloys with large thin-walled shape were continuously processed by coupling travelling magnetic fields(TMF)with sequential solidification,to eliminate the shrinkage defects and optimize the mechanical performa...ZL205 A alloys with large thin-walled shape were continuously processed by coupling travelling magnetic fields(TMF)with sequential solidification,to eliminate the shrinkage defects and optimize the mechanical performance.Through experiments and simulations,the parameter optimization of TMF and the influence on feeding behavior,microstructure and properties were systematically studied.The results indicate that the magnetic force maximizes at the excitation current of 20 A and frequency of 200 Hz under the experimental conditions of this study,and increases from center to side-walls,which is more convenient to process thin-walled castings.TMF can break secondary dendritic arm and dendrites overlaps,widen feeding channels,prolong the feeding time,optimize the feeding paths,eliminate shrinkage defects and improve properties.Specifically,for as-cast state,TMF with excitation current of 20 A increases ultimate tensile strength,elongation and micro-hardness from 186 MPa,7.3%and 82.1 kg/mm^(2) to 221 MPa,11.7%and 100.5 kg/mm^(2),decreases porosity from 1.71%to 0.22%,and alters brittle fracture to ductile fracture.展开更多
文摘In the light of the bronzes so far unearthed from the Yin Ruins and their casting technology known through researches,the present paper studies the bottom mold of large-sized bronze vessels unearthed from Xiaomintun on the Yin Ruins in the excavation of 2003 to 2004,and affirms its casts to have been large-sized bronze pan basins.Taking into account related historical records and oracle-bone inscriptions,the author concludes that Shang and Zhou bronze pan were all wash-vessels and a little differed from each other in use.Moreover,during the Shang-Zhou period,there was intricate washing ritual,including not only ceremonious actions of face,hair and hand washing,but also those of all body bathing in large-sized pan in the case of grand sacrificial activities.
基金financial supports from the National Key Research and Development Program of China(2017YFA0403804)the National Natural Science Foundation of China(51425402,51671073)。
文摘ZL205 A alloys with large thin-walled shape were continuously processed by coupling travelling magnetic fields(TMF)with sequential solidification,to eliminate the shrinkage defects and optimize the mechanical performance.Through experiments and simulations,the parameter optimization of TMF and the influence on feeding behavior,microstructure and properties were systematically studied.The results indicate that the magnetic force maximizes at the excitation current of 20 A and frequency of 200 Hz under the experimental conditions of this study,and increases from center to side-walls,which is more convenient to process thin-walled castings.TMF can break secondary dendritic arm and dendrites overlaps,widen feeding channels,prolong the feeding time,optimize the feeding paths,eliminate shrinkage defects and improve properties.Specifically,for as-cast state,TMF with excitation current of 20 A increases ultimate tensile strength,elongation and micro-hardness from 186 MPa,7.3%and 82.1 kg/mm^(2) to 221 MPa,11.7%and 100.5 kg/mm^(2),decreases porosity from 1.71%to 0.22%,and alters brittle fracture to ductile fracture.
