《工程科学学报》录用稿，htps:/doi.org/10.13374/i,issn2095-9389.2021.01.16.002©北京科技大学2020 冷冻铸造A356铝合金微观组织分析 杨浩秦13，单忠德3，刘丰23，王怡飞23 (1.南京航空航天大学材料科学与技术学院，南京，210016：2.机械科学研究总院集团有限公司，北京，100044 3.先进成形技术与装备国家重点实验室，北京，100083) 摘要：本文基于数字化无模冷冻铸造精密成形技术实现了冷冻砂型的快速成形，对其浇注A356高温铝合 金获得冷冻铸造平板试件。采用电子探针显微分析技术对冷冻铸造和树脂砂型铸造铸件微量元素的分布进 行了表征，同时对冷冻铸造和树脂砂型铸造铸件断裂形貌进行了分析。结果表明，冷冻铸造S元素在铝基 体相中的溶解度较树脂砂型铸造显著提高，冷冻铸造较树脂砂型铸造试件中Mg元素分布均匀，树脂砂型 铸造试件中出现较多的Mg元素成分偏析区：冷冻铸造试件断口形貌为韧性和脆性的混合断裂模式，树脂 砂型铸造试件的断裂形貌为解理台阶破坏形貌和长方状的撕裂结构形貌，合金偏向于脆性海 关键词：诊冻铸造：模成形：：无模成形，一绿色铸造：一成分分布：：断日形貌 中图法分类号：TG146.22文献标识码：A文章编号： Microstructure analysis of freeze-cast A356 aluminum alloy YANG Haoqin 3,SHAN Zhongde,LIU Feng2,WANG Yifei2 (1.Nanjing University of Aeronautics and Astronautics,College of Materials Science and Technology,Nanjing,210016;2.China Academy of Machinery Science and Technology Group Co.Itd,Beijing,10044 3.State Key Laboratory of Advanced Forming Technology and Equipment,Beijing,100083) Abstract:In combination with the digital and green development needs of the foundry industry,this article innovatively proposes a digital patternless freezing casting method.The principle is that the mixed water green sand particles are frozen and transformed to a certain strength in a low temperature environment. and then directly cut through the sand mold CAD three-dimensional model.Pouring to obtain castings with dimensional accuracy that meets the requirements.it is a new technology,new process and new method in the field of casting.With the rapid development of rapid and sub-rapid solidification technology of metals. the noqi solidificationthyof liquid-solid transformationuring thepreparation of metals and alloy materials has been developed by leaps and bounds.Using some special non-equilibrium solidifcation techniquemetal parts,and to make the metal parts have a special structure and structure that traditional casting does not have,is a way to improve the properties of materials and structures.The non-equilibrium solidification mechanism based on the freezing casting technology is not clear yet.based on the non-equilibrium solidification process of the freezing casting principle,a higher cooling rare win significantly affect the heat transfer and mass transfer behavior of the casting during solidification,and then have a significant impact on the alloy micro-component distribution and fracture morphology,and ultimately affect the service performance of the alloy material.Based on the digital precision forming technology of patternless frozen casting.this paper realized the rapid forming of frozen sand mold,the frozen casting flat castings were obtained by pouring A356 high temperature aluminum alloy.The distribution of trace elements in frozen casting and resin sand casting castings was characterized by electron probe microanalysis,and the fracture morphology of frozen casting and resin sand castings was analyzed.The results show that the solubility ement in aluminum matrix phase of freeze casting is significantly higher than that of r and casting the distr of Mg element in freeze casting is more uniform than that in resin sand casting,and there are more segregati areas of Mg element composition in resin sand casting specimens.The fracture morphology of freeze-cast specimens is a mixed fracture mode of toughness and brittleness,while the fracture morphology of resin sand casting specimens is cleavage step failure morphology and rectangular tear structure冷冻铸造 A356 铝合金微观组织分析 杨浩秦 1,3，单忠德 1,3，刘丰 2,3，王怡飞 2,3 (1.南京航空航天大学材料科学与技术学院，南京，210016；2.机械科学研究总院集团有限公司，北京，100044 3.先进成形技术与装备国家重点实验室，北京，100083） 摘要：本文基于数字化无模冷冻铸造精密成形技术实现了冷冻砂型的快速成形，对其浇注 A356 高温铝合 金获得冷冻铸造平板试件。采用电子探针显微分析技术对冷冻铸造和树脂砂型铸造铸件微量元素的分布进 行了表征，同时对冷冻铸造和树脂砂型铸造铸件断裂形貌进行了分析。结果表明，冷冻铸造 Si 元素在铝基 体相中的溶解度较树脂砂型铸造显著提高，冷冻铸造较树脂砂型铸造试件中 Mg 元素分布均匀，树脂砂型 铸造试件中出现较多的 Mg 元素成分偏析区；冷冻铸造试件断口形貌为韧性和脆性的混合断裂模式，树脂 砂型铸造试件的断裂形貌为解理台阶破坏形貌和长方状的撕裂结构形貌，合金偏向于脆性断裂。 关键词：冷冻铸造; 模成形; ；无模成形；绿色铸造; ；成分分布; ；断口形貌 中图法分类号：TG146.22 文献标识码： A 文章编号： Microstructure analysis of freeze-cast A356 aluminum alloy YANG Haoqin1,3, SHAN Zhongde1,3, LIU Feng2,3, WANG Yifei2,3 (1. Nanjing University of Aeronautics and Astronautics,College of Materials Science and Technology, Nanjing, 210016; 2.China Academy of Machinery Science and Technology Group Co.Itd, Beijing ,100044; 3. State Key Laboratory of Advanced Forming Technology and Equipment, Beijing ,100083) Abstract: In combination with the digital and green development needs of the foundry industry, this article innovatively proposes a digital patternless freezing casting method. The principle is that the mixed water green sand particles are frozen and transformed to a certain strength in a low temperature environment, and then directly cut through the sand mold CAD three-dimensional model. Pouring to obtain castings with dimensional accuracy that meets the requirements, it is a new technology, new process and new method in the field of casting. With the rapid development of rapid and sub-rapid solidification technology of metals, the non-equilibrium solidification theory of liquid-solid transformation during the preparation of metals and alloy materials has been developed by leaps and bounds. Using some special non-equilibrium solidification techniques to prepare metal parts, and to make the metal parts have a special structure and structure that traditional casting does not have, is a way to improve the properties of materials and structures. The non-equilibrium solidification mechanism based on the freezing casting technology is not clear yet, based on the non-equilibrium solidification process of the freezing casting principle, a higher cooling rate will significantly affect the heat transfer and mass transfer behavior of the casting during solidification, and then have a significant impact on the alloy micro-component distribution and fracture morphology, and ultimately affect the service performance of the alloy material . Based on the digital precision forming technology of patternless frozen casting, this paper realized the rapid forming of frozen sand mold, the frozen casting flat castings were obtained by pouring A356 high temperature aluminum alloy. The distribution of trace elements in frozen casting and resin sand casting castings was characterized by electron probe microanalysis, and the fracture morphology of frozen casting and resin sand castings was analyzed. The results show that the solubility of Si element in aluminum matrix phase of freeze casting is significantly higher than that of resin sand casting, the distribution of Mg element in freeze casting is more uniform than that in resin sand casting, and there are more segregation areas of Mg element composition in resin sand casting specimens. The fracture morphology of freeze-cast specimens is a mixed fracture mode of toughness and brittleness, while the fracture morphology of resin sand casting specimens is cleavage step failure morphology and rectangular tear structure 《工程科学学报》录用稿，https://doi.org/10.13374/j.issn2095-9389.2021.01.16.002 ©北京科技大学 2020 录用稿件，非最终出版稿