Effects of Die Corner Radius and Temperature on the Formability of AA7075-T6 Alloy

doi:10.1007/s40195-013-0129-5

Abstract

Abstract:

This study focused on the　formability of aluminium alloy (7075-T6) sheets through hydroforming　route. Formability of these sheets was tested using a warm forming　setup at three different temperatures and four different die corner　radii. Forming limit diagrams (FLD) were generated by measuring the　grids of the sheet formed. The results show that the forming limit　of AA7075-T6 can be significantly improved when the blank was heated　to 140－250℃. It was also observed that as the temperature increases above 140℃, dome height began to decrease. Also the results indicated that both the die corner radius and temperature have a significant effect on the stress-strain curve and warm forming of AA7075-T6 sheets. Thus, with the temperature increased from room temperature (RT) to 140℃, the flow stress decreased and the strain increased, hence, the formability is enhanced. However, further increase in temperature causes decreases the flow stress and strain. Similar changes of the flow curve were seen in die corner radius. Decreasing the die corner radius decreases the flow stress and increase the strain. Moreover, an equation was obtained by establishing correlations between the experimental parameters and their results. In this way, it became possible to make predictions.

Key words: Al-Zn-Mg-Cu Alloy, Drawing process, Formability, Forming limit Curve, Deformation

Hatice Evlen, I brahim Kadι, Mustafa Yasar. Effects of Die Corner Radius and Temperature on the Formability of AA7075-T6 Alloy[J]. Acta Metallurgica Sinica (English Letters), 2013, 26(5): 623-629.

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