The pressing process,as compared to the machining process,makes good utilization of work piece material and shortens the production time,and as such it is increasingly used for production of complex shaped parts.A par...The pressing process,as compared to the machining process,makes good utilization of work piece material and shortens the production time,and as such it is increasingly used for production of complex shaped parts.A particular type of pressing is sheetextrusion which controls the flow of material into special punch and die sets to produce an extruded shape.However,some particularly complex shaped parts cannot be made by sheet-extrusion due to the formation of piping defects.In this study,the finite element method(FEM)was used to investigate the formation of piping defects.In addition,the relationship between the characteristic dimensions of the extruded shape and the piping defect was also examined.Laboratory pressing experiments were performed to validate the accuracy of the FEM simulation results.Based on the stress distribution and velocity profiles within the extruded work piece,the relationship between the extruded shape and the piping defect was clearly identified.Furthermore,the FEM simulation results showed good agreement with the experimental results with regards to the dimensions of the extruded shape and the piping defect.展开更多
基金This research was partially supported by a Grant from the Thai-German Institute(TGI)under Grant No.S2-CD-03/2554 and the Higher Education Research Promotion and National Research University Project of Thailand,Office of the Higher Education Commission,under Grant No.56000519 and Grant No.57000618.The authors would also like to thank Mr.Arkarapon Sontamino and Mr.Pakkawat Komolruji for their assistance during this study。
文摘The pressing process,as compared to the machining process,makes good utilization of work piece material and shortens the production time,and as such it is increasingly used for production of complex shaped parts.A particular type of pressing is sheetextrusion which controls the flow of material into special punch and die sets to produce an extruded shape.However,some particularly complex shaped parts cannot be made by sheet-extrusion due to the formation of piping defects.In this study,the finite element method(FEM)was used to investigate the formation of piping defects.In addition,the relationship between the characteristic dimensions of the extruded shape and the piping defect was also examined.Laboratory pressing experiments were performed to validate the accuracy of the FEM simulation results.Based on the stress distribution and velocity profiles within the extruded work piece,the relationship between the extruded shape and the piping defect was clearly identified.Furthermore,the FEM simulation results showed good agreement with the experimental results with regards to the dimensions of the extruded shape and the piping defect.
