Controlled directionality of mechanical properties in sheet metals

Abstract

Techniques of manufacture that are aimed at developing directional properties in materials matching the directional requirements of their application have provided a recurrent theme in metallurgy. The subject now involves such diverse techniques as controlled mechanical working, directional solidification, and the production of fibre-strengthened composites. However, so far as mechanical properties are concerned, the majority of established methods depend for their success mainly on a controlled distribution of strong and ductile phases within the aggregate, rather than on the presence of preferred crystallographic orientations. At present, practical interest in controlling crystallographic textures as a means of improving mechanical behaviour is centred on applications to ductile wrought metals. The review is concerned with progress in this particular field. Most of the examples considered relate to sheet metals and alloys used in cold forming, many of which are at least approximately single-phase aggregates. In such materials strong preferred crystallographic orientations can be developed rather easily by suitable cold working and recrystallisation procedures. However, it is worth emphasising that applications of the principles involved need not be confined either to single-phase alloys or to sheet materials.