DIN EN ISO 10275:2014-08

ISO 10275:2007 specifies a method for determining the tensile strain hardening exponent n of flat products (sheet and strip) made of metallic materials.The method is valid only for that part of the stress-strain curve in the plastic range where the curve is continuous and monotonic (see 7.4). In the case of materials with a serrated stress-strain curve in the work hardening range (materials which show the Portevin-Le Chatelier effect, e. g. AlMg-alloys) the automatic determination (linear regression of the logarithm true stress vs. the logarithm true plastic strain, see 7.7) should be used to give reproducible results.