Dissemination of IT for the Promotion of Materials Science (DoITPoMS)

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Effect of Texture

Mechanical properties

The effects of anisotropy can either cause problems for the mechanical properties of metals, or they can be exploited to the benefit of the manufacturer.

The phenomenon of “earing” in deep drawing, where a wavy edge forms on the top of a drawn cup, allows the effect of texture to be seen easily. Depending on the degree of preferred orientation, two, four or six ears will form and extensive trimming is required to produce a uniform top. However, in beverage can and automobile body manufacture, plastic instability is avoided by controlling the texture in the thickness direction. This allows for very thin sheets to be produced without fracture.

Magnetic properties

In transformers, the texture of grain-oriented silicon steel (GOSS steel) is controlled to minimise core loss.Two textures can be developed in silicon steels: the cube on face or {001}<100> texture in which a {001} plane lies in the sheet plane, or the cube on edge {011}<100> texture (also known as the Goss texture, after its discoverer, Norman P. Goss) in which a {011} plane lies in the sheet plane. The Goss texture arises initially as a small component during rolling, but forms large grains during recrystallisation. By promoting the development of the Goss texture, the magnetic flux density can be increased by up to 30% relative to steel without this texture.