The Experimental Investigation of Springback in V-Bending Using the Flexforming Process


ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING, vol.42, no.5, pp.1853-1864, 2017 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 42 Issue: 5
  • Publication Date: 2017
  • Doi Number: 10.1007/s13369-016-2329-6
  • Page Numbers: pp.1853-1864


The flexforming process is a sheet metal forming method that uses hydraulic fluid pressure and a rubber diagram to form sheet metal with a die. This study, for the first time, experimentally investigates the factors affecting the springback resulting from the bending of copper and brass sheet metal materials in V-bending dies using the flexforming process. Additionally, the formability during the V-bending method was experimentally investigated by using thin, high-pressure-resistant rubber membranes instead of the thick ones commonly used in the flexforming processes. The process parameters in the experimental studies were determined to be: holding time (0, 5 and 10 s), bending angle (15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees and 90 degrees) and fluid pressure (10, 12 and 14.4 MPa). Sheet metals were formed in V-bending dies by both flexforming and conventional bending processes to compare the performance of the flexforming process against the conventional bending process. Springback values in the parts formed using the flexforming process for copper and brass sheet metals were determined to be 39.06 and 41.42% less, respectively, than those formed by the conventional bending method. Surface flaws occurring in the parts formed by the conventional bending method were not observed in the parts formed using the flexforming process. The springback was also estimated by using fuzzy logic based on unexecuted break-test parameters. When the outputs of the fuzzy logic system were compared with the experimental results, it was observed that the results were substantially similar.