The effect of material properties on the initiation of wrinkling and on wrinkle height at 2% mean axial extension of a range of sheet metals was investigated using the Yoshida or 'handkerchief' test. It was found that the onset of wrinkling was accelerated by strain rate, normal plastic anisotropy and by yield strength, but was delayed by increase in L??ders strain (yield elongation) when present, by work hardening and by positive strain-rate sensitivity. The growth of wrinkles was retarded by L??ders strain, work hardening, by high values of the ratio r*/YS and of the coefficient of strain-rate sensitivity, but was promoted by increasing yield strength. Initiation of wrinkling occurred later when the upper yield point had not been removed, but growth was more rapid. Growth was slower when L??dering had been removed: hence in industrial practice, the usual procedure of temper rolling before sheet forming might be disadvantageous in those applications in which L??ders bands (stretched strains) on the product could be tolerated. The close correlations obtainable for the same or similar materials in different conditions confirm the usefulness of the Yoshida test for comparing these materials with respect to the onset and growth of wrinkles, whereas the test appears less useful for rating the wrinkling behaviour of materials of different types because of unaccounted factors. ?? 1984.
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