Title

SERRATION BEHAVIOR OF AA5182/POLYPROPYLENE/AA5182 SANDWICH SHEETS.

Authors

KEE JOO KIM; JOO SUNG KIM

Abstract

The examination of serration behavior has been made after the tensile deformation of the AA/PP/AA sandwich sheets as well as that of the 5182 aluminum skins. All sandwich sheets and the 5182 aluminum skin showed serration behavior on their flow curves. However, the magnitude of serration was significantly diminished in the sandwich sheet with high volume fraction of the polypropylene core. According to the results of the analysis of the surface roughness following the tensile test, Lüders band depth of the sandwich sheet evidently showed lower than that of the 5182 aluminum skin. The strain rate sensitivity, m-value, of the 5182 aluminum skin was -0.006. By attaching these skins to the polypropylene core, which has relatively large positive value of 0.050, m-value of the sandwich sheets changed to a positive value. The serration reduction of the sandwich sheets was quantitatively investigated with respect to the effect on polypropylene thickness variation, that on the strain rate sensitivity and that on the localized stress state. It was found that the serration reduction degree from the experimental results of the sandwich sheet was higher than from the calculated values by the rule of mixture based on the volume fraction of the skins and the core.

Subjects

ALUMINUM; SHEET metal; LUDERS bands; STRAINS & stresses (Mechanics); STRESS-strain curves; POLYPROPYLENE; THERMOPLASTICS

Publication

International Journal of Modern Physics B: Condensed Matter Physics; Statistical Physics; Applied Physics, 2006, Vol 20, Issue 25-27, p4316

ISSN

0217-9792

Publication type

Academic Journal

DOI

10.1142/S0217979206041288