Effect of Strain-Rate and Temperature on Yield Locus for 5083 Aluminum Alloy Sheet

Abstract

To determine yield locus of type 5083 aluminum-magnesium sheet at elevated temperature, biaxial tensile experiments were performed, using cruciform specimens, at various temperatures (25 -300 ℃) at strain rates raging from 10 -5 to 10 -2 s -1 . From the experimental results, the effects of strain rate and temperature on the yield locus are discussed. The size of yield locus drastically decreased with increasing temperature and with decreasing strain rate. Neither von Mises' yield criterion or Hill's can well predict the shape of yield locus of this type of sheet metal. In contrast, the yield criterion of Logan-Hosford or Barlat well simulate the yield locus at elevated temperatures.

Effects of strain rate, temperature and sheet thickness on yield locus of AZ31 magnesium alloy sheet

“…M is a material constant, where M = 10 was selected for the AZ31 sheets (cf., for aluminum sheet (Naka et al, 2004)). The experimental results of the r-values, measured with strain gages, are summarized in Fig.…”

“…The present authors have recently developed an experimental technique of biaxial stretching of cruciform specimens and published a paper showing the experimental data of yield loci of aluminum alloy sheet at elevated temperature (Naka et al, 2004). Using this technique, in the present work, the effects of forming speed, temperature and sheet thickness on the shape and size of yield loci were experimentally investigated for fine-grain AZ31 magnesium alloy sheets.…”

Advances in anisotropy and formability

“…Moreover, it is not easy to create this geometry using as-received metal sheets a few mm thick, common thickness in sheet forming industry. The Type C specimens [52,128,178,222] can be made of as-received sheet materials, although (C1) type specimens [52,128] require welding for fixing thin strips (arms) to the gauge section. The merit of the Type C specimens is that it is simple to determine biaxial stress components in the gauge section by virtue of slits in the arms or welded thin strips.…”

Characterization of yielding behavior of sheet metal under biaxial stress condition at elevated temperatures

“…The comparison of the experimental results determined with the LFT-setup and Naka et al [19] at elevated temperatures is illustrated in Fig. 10 and shows a very good agreement for the different databases.…”

“…As explained, for the evaluation of the LFT-results a methodology based on a statistical function is applied on the measurement data. Since Naka does not give any information on this aspect, it is assumed that the sum of plastic work W p0,2 has been used as it has been done in comparable work [19]. Based on this compliance the LFT-setup is qualified for the experimental determination of yield loci for biaxial tensile stress conditions as can be seen in the good correlation of the values in Fig.…”