Experimental investigation of the effects of annealing in Al7075-T6 sheet metal material on formability and springback


KARAAĞAÇ İ. , KABAKÇI M. O. , Demirel M. Y.

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, vol.36, no.3, pp.1320-1329, 2021 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 36 Issue: 3
  • Publication Date: 2021
  • Doi Number: 10.17341/gazimmfd.647009
  • Title of Journal : JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY
  • Page Numbers: pp.1320-1329

Abstract

In this study, the formability and spring-back behavior of Al7075-T6 sheet material were experimentally investigated using a V-bending process, depending on the annealing parameters. Annealing processes were applied at different annealing temperatures (100 degrees C, 200 degrees C, 300 degrees C, and 400 degrees C) and holding times (6, 30, and 60 minutes). The formability of the annealed Al 7075-T6 specimens were investigated by bending at a constant deformation velocity with 15 degrees, 30 degrees, 45 degrees, 60 degrees, and 75 degrees degrees angled V bending dies. Besides, depending on the increase in the annealing time on the annealed samples, precipitation was observed with a 300 degrees C annealing temperature. Depending on the increasing annealing temperature, an increase in grain size and a decrease in hardness were observed. While the hardness values of the non-annealed specimens were 200.67 HV at room temperature (RT), but also it was observed that the hardness of the specimens annealed at 400 degrees C for 60 minutes decreased to 62.90 HV. According to this situation, unannealed specimens can be formed by V-bending up to 15 degrees bending angle, while specimens annealed at 300 degrees C and above can be formed successfully without cracking and breaking even at 75 degrees bending angle. It was observed that the spring-back behavior of specimens annealed at high temperatures occurred at a rate of 80-90% less compared to specimens that were annealed at low temperatures.