Formation of Surface Texture and Anisotropy of Shape Memory Effect in an Fe-Mn-Si Alloy

Abstract

Formation of surace texture and its influence on shape memory effect in an Fe-Mn-Si alloy have been investigated, using specimens taken from the surface layer and from the central layer of the hot rolled sheet produced using a low-tempperature finishing. It was found that a shear texture with a major component of {001}<110> was formed in the surface layer of the sheet, resulting in a marked anisotropy of shape recovery strain, while a pure metal type rolling texture was formed in the mid-thickness, leading to a less anisotropy. A maximum of shape recovery strain at a given prestrain is obtained for the specimens with tensile axes parallel to the rolling direction (RD) or the transverse direction to the RD in the plane of the surface layer, i.e. the specimens with their tensile axes preferentially oriented to <110>. This suggests the possibility of improvement in shape memory effect of the whole sheet by a further spreading if the surface texture towards the central layer of the sheet if the rolling process is optimized.