An effect of unequal deformation in development of advanced plasticprocessing technologies is researched by studying an in-plane bending process of strip metal underunequal compressing. The research results show the f...An effect of unequal deformation in development of advanced plasticprocessing technologies is researched by studying an in-plane bending process of strip metal underunequal compressing. The research results show the following: If appropriately controlled, unequalplastic deformation can play an important role not only in the improvement of quality of partsobtained by plastic processing technologies, but also in the development of new processes foradvanced plastic working technologies. A coordinated growth of unequal plastic deformation candevelop the deformation potentiality of material to the fall. The degree of unequal plasticdeformation can be used as bases for optimization design of processes and dies of plastic forming.展开更多
The fabrication of near-net-shaped objects of RE123 superconductors by 'infiltration processing' is discussed. Near-net-shape processing involves the infiltration of preshaped porous green bodies of either 211...The fabrication of near-net-shaped objects of RE123 superconductors by 'infiltration processing' is discussed. Near-net-shape processing involves the infiltration of preshaped porous green bodies of either 211 or yttria phases by liquids containing barium cuprates and copper oxides followed by a controlled peritectic solidification. The process yields poly- and also single-crystalline superconducting objects with a shrinkage of less than half of one percent of the green bodies. The preservation of the initial structure of the green bodies results in fabrication of RE 123 in a wide variety of dimensions and complex shapes. The demonstrated products include bulk components like cylinders, single domain thick films on a variety of substrates, freestanding fabrics and open porous superconducting foams. This paper presents a comprehensive description of the infiltration processing technique and the resulting microstructures of the superconducting bodies. The advantages of this technique and practical applications of the processed superconducting structures are highlighted.展开更多
激光近形制造技术(1aser engineered net shaping,LENS)是一种低成本、快速制作高性能全致密金属零件的技术。采用不同的激光烧结参数研究了镍基合金的激光快速烧结成形。利用显微硬度分析和金相分析研究了扫描速度、激光功率、离焦...激光近形制造技术(1aser engineered net shaping,LENS)是一种低成本、快速制作高性能全致密金属零件的技术。采用不同的激光烧结参数研究了镍基合金的激光快速烧结成形。利用显微硬度分析和金相分析研究了扫描速度、激光功率、离焦量、送粉气流量对薄壁组织及性能的影响。微观组织观察表明,成形件组织致密,发育有枝状晶体等快速凝固组织所具有的特征。制件的平均显微硬度(HV)在1.35~1.90 GPa之间。通过实验得到了一组优化的工艺参数,并由此烧结出了结构致密、显微硬度较高的薄壁器件。展开更多
基金National Natural Science Foundation of China (No.59475059) and the Aeronautical Science Foundation of China (No.94G53111).
文摘An effect of unequal deformation in development of advanced plasticprocessing technologies is researched by studying an in-plane bending process of strip metal underunequal compressing. The research results show the following: If appropriately controlled, unequalplastic deformation can play an important role not only in the improvement of quality of partsobtained by plastic processing technologies, but also in the development of new processes foradvanced plastic working technologies. A coordinated growth of unequal plastic deformation candevelop the deformation potentiality of material to the fall. The degree of unequal plasticdeformation can be used as bases for optimization design of processes and dies of plastic forming.
基金German Federal Ministry of Higher Education and Research(BMBF)(No.13N1571/l)
文摘The fabrication of near-net-shaped objects of RE123 superconductors by 'infiltration processing' is discussed. Near-net-shape processing involves the infiltration of preshaped porous green bodies of either 211 or yttria phases by liquids containing barium cuprates and copper oxides followed by a controlled peritectic solidification. The process yields poly- and also single-crystalline superconducting objects with a shrinkage of less than half of one percent of the green bodies. The preservation of the initial structure of the green bodies results in fabrication of RE 123 in a wide variety of dimensions and complex shapes. The demonstrated products include bulk components like cylinders, single domain thick films on a variety of substrates, freestanding fabrics and open porous superconducting foams. This paper presents a comprehensive description of the infiltration processing technique and the resulting microstructures of the superconducting bodies. The advantages of this technique and practical applications of the processed superconducting structures are highlighted.
文摘激光近形制造技术(1aser engineered net shaping,LENS)是一种低成本、快速制作高性能全致密金属零件的技术。采用不同的激光烧结参数研究了镍基合金的激光快速烧结成形。利用显微硬度分析和金相分析研究了扫描速度、激光功率、离焦量、送粉气流量对薄壁组织及性能的影响。微观组织观察表明,成形件组织致密,发育有枝状晶体等快速凝固组织所具有的特征。制件的平均显微硬度(HV)在1.35~1.90 GPa之间。通过实验得到了一组优化的工艺参数,并由此烧结出了结构致密、显微硬度较高的薄壁器件。