The cavitation behavior of a coarse-grained A15052 alloy under hot uniaxial and equibiaxial tension

In this paper, the cavitation behavior of a commercially available coarse-g rained Al5052 alloy under hot uniaxial and equibiaxial tension was studied for the first time. Tensile specimens were strained to different strain lev els at various initial strain rates and temperatures. The results revealed that there was no significant difference in the cavitation size distributio n under different stress states, and the spread of cavity size and the tota l number of cavities were found to increase with increasing strain. In micr ostructural examination, some voids were observed at the interface between the intermetallic particles and the matrix, and they were growing continuou sly with increasing strain. Quantitative analysis revealed that the cavity growth was essentially plasticity-controlled. A lower cavitation growth rat e was observed for the Al5052 alloy as compared to that of the superplastic Al5083 alloy, which could not explain the relatively low elongation value of 194% of Al5052. It was considered that the hot formability of Al5052 did not only relate to its cavitation behavior, but also its strain rate sensi tivity value. (C) 2001 Elsevier Science B.V. All rights reserved.