Texture and anisotropy of polycrystalline materials – Formation of textures

The scientific and industrial importance of mastering the textures of polycrystalline materials is due to the consequences of textures:

• on the formability of sheet metals,

• and on the shaping and properties of highly anisotropic alloys, especially hexagonal materials such as zinc, zirconium and titanium.

Optimizing the texture of the fini product improves its properties for use. Notable examples include cladding tubes for nuclear fuel, soft magnetic laminations, hard magnetic materials, high-temperature superconductors, ceramic substrates and many others. Aluminium alloy 1050 (99.5% aluminium or aluminium A5) is commonly used in sheet metal work where strength requirements are moderate, not least for its high electrical conductivity. In particular, the manufacture of electrolytic capacitors requires the development of a very pronounced cube texture. The austenitic Fe-Ni36% alloy known as "Invar®" is used in electronic devices due to its low coefficient of thermal expansion and good magnetic properties. For this purpose, it is advantageous to have a high cube orientation fraction. HSLA (High Strength Low Alloy) micro-alloyed steel produced by thin-strip casting is of great industrial interest, not least because hardening is achieved by precipitation and grain-size refinement.

This article details the mechanisms by which crystallographic textures are formed in materials. It follows the article [M 3 040] "Definitions and experimental techniques", which details the tools for quantitatively determining crystallographic textures. It will be followed by [M 3 042] "Properties of textured materials", which provides tools for calculating the anisotropic properties of polycrystalline materials, and for optimizing the properties of these materials.