Dynamic Mechanical Properties of Automotive Thin Sheet Steel in Tension, Compression and Shear

Abstract: Thin sheet steel has been tested at different strain rates ranging (10 " to s- ' ) under different deformation modes. The specimens were cut from thin sheet at 0 and 90 degrees with respect to the rolling direction. It was found that pre-strained specimens in tension are characterised by higher initial yielding and a strong decrease of the strain hardening. Specimens at 90 degrees show at increasing strain rate a higher yielding stress with respect to 0 degrees specimens emphasising the importance of anisotropy effects in sheet metals. Furthermore, the equivalent flow curve at relatively large strain values do not coincide at different deformation modes (shear, compression and tension). RkumC: Une t61e mince a it6 testee A differentes vitesses (10 " a 10 " is) et modes de deformation. Les kchantillons ont t t t dkcoupks A 0 et 90 degres par rapport a la direction de laminage. Les echantillons predeformds en traction montrent une augmentation de la contrainte d'tcoulement et une diminution de I'ecrouissage. Les tchantillons dkcoupes A 90 degres rnontrent que la valeur de la contrainte d'ecoulement est plus sensible i la vitesse de deformation par rapport a ceux decoupes a 0 degre ce qui montre I'importance des effets d'anisotropie dans les tBles minces. De plus, la contrainte d'ecoulement equivalente aux fortes deformations ne co'incide pas pour les diffkrents modes de sollicitation (cisaillement, compression et traction). 1.