Working Conditions for Improving Pure Stretchability of Sheet Metals : The Effect of Punch Profile

• KOBAYASHI Masanori

• KUROSAKI Yasushi

• KAWAI Nozomu

Abstract

Strengthening of pressed components has recently been reqired to husband natural resources and save energy. Unfortunately, any strengthening of sheet metals generally causes a decrease in their ductility and formability. Therefore, it is very important to find out the optimum forming conditions. In the present study, the optimum conditions for increasing the critical forming depth in pure stretch forming are clarified, using several punches with an ellipsoidal profile, seven kinds of sheet metals and four kinds of lubricants. The optimum punch profile and the optimum frictional coefficient for increasing the critical forming depth were found by both numerical analysis and experiments. In addition, it was confirmed that the critical forming depth could be increased by applying a low friction lubricant (PTFE and Bright stock) to the central region of the punch and a high friction lubricant (Rosin) at the outer region.

Journal

• Bulletin of JSME

  Bulletin of JSME 25 (208), 1634-1642, 1982

  The Japan Society of Mechanical Engineers

Keywords

• Forming
• Sheet Metal
• Pure Stretch Forming
• Effect of Punch Profile
• Optimum Condition
• Frictional Coefficient
• n-value
• r-value

Details

• CRID: 1390001206492914816
• NII Article ID: 110002359854
• NII Book ID: AA0058509X
• DOI: 10.1299/jsme1958.25.1634
• ISSN: 18811426
• ISSN: 00213764
• HANDLE: 10076/8686
• Web Site: https://mie-u.repo.nii.ac.jp/records/8260
• Web Site: http://www.jstage.jst.go.jp/article/jsme1958/25/208/25_208_1634/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • IRDB
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed