报告题目: Progressive and compound forming of bulk micro-scaled by using sheet metals

报告时间: 2020年1月18日10:00-11:30

报告地点: 我院334会议室

报告人: 傅铭旺教授

报告人简介: 傅铭旺，香港理工大学机械工程学院教授，塑性加工领域国际知名专家，主要研究综合产品设计与工艺研发，金属成形与模具设计，微细精密零部件的制造及先进材料微细成形加工。担任Int. J. Plasticity、Mater. Design、Int. J. Damage Mech.、Int. J. Adv. Manuf. Tech.、中国机械工程-英文版等多个SCI权威期刊编委，也是多个SCI期刊、重大奖项评比及项目课题申报的特邀评审人。现已在IJP、IJMTM、JMPT等顶级/权威期刊发表SCI论文160余篇，其中塑性领域TOP1期刊IJP 14篇，出版英语专著5部，多篇学术论文被著名的国际微制造会议授予“最佳论文奖”以及多篇学术论文被Web of Science TM评为“SCI高被引论文”。

报告内容简介：

The most critical issues in microforming technologies are tailoring the desirable product quality and ensuring the high productivity from application perspective. To realize batch micromanufacturing of the flanged microparts, an efficient progressive microforming method is proposed by using an integrated hole flanging-ironing process. In this process, size effect and its affected deformation behavior, forming quality and ductile fracture of the micropart are still not well known. In addition, the ductile fracture behavior of work material is induced by the accumulated degradation of material stiffness when plastic deformation level reaches a certain limit, which is liable to occur due to the accumulated deformation in progressive flanging-ironing process. The unique accumulative deformation behavior and its affected ductile fracture is closely related to the forming quality and defect formation in the progressive microforming. This study thus aims at addressing these issues in terms of dimensional accuracy, accumulative deformation, defect formation and ductile fracture based on an unequal-thickness flanged micropart produced by the developed progressive microforming system in which shearing, hole flanging-ironing and blanking operations are realized progressively. The experimental and simulative results reveal that the dimensional accuracy of the flanged micropart is aggravated with the increasing grain size due to the coupled effect of free surface roughening and interfacial friction. The fracture phenomenon at the flanged tips show the increasing trend with the decreasing number of grains over the thickness of workpiece. Through realization and examination of the developed progressive microforming system and the finished microparts, the progressive micro flanging-ironing process is proven to be promising and efficient for mass micromanufacturing of micro flanged parts.