Simple models in literature [K.F. Chiang, Cold roll forming, ME Thesis, University of Auckland, August 1984] predict that the longitudinal peak membrane strain in the flange of a profile is independent of the material properties. However, Ingvarsson [L. Ingvarsson, Förenklad teori för rullforming av elementär v-profil, jämförelse mellan normalt och höghållfast stål, VAMP 15- rullforming 23 april 2001] compared mild and ultra high strength in a roll forming experiment and the conclusion was that the material properties will affect the finished profile. This paper is a fundamental study performed in order to understand the observation by Ingvarsson [L. Ingvarsson, Förenklad teori för rullforming av elementär v-profil, jämförelse mellan normalt och höghållfast stål, VAMP 15- rullforming 23 april 2001].
The objectives of this study are to investigate the change in the longitudinal peak membrane strain at the flange edge and the deformation length when the yield strength increases. These are important since they can be used to determine the number of forming steps and the distance between them when designing the cold roll forming machine. The result from the simulations show that the longitudinal peak membrane strain decreases and the deformation length increases when the yield strength is increased.