Grain size strengthening

In addition to these principal alloying elements, which provide soHd solution strengthening and/or precipitation strengthening, wrought alloys may contain small amounts of titanium and boron [7440-42-8J, B, for control of ingot grain size, and ancillary additions of chromium, manganese, and zirconium to provide dispersoids. AH commercial alloys also contain iron and siUcon. 

Honeyman-Colvin, P., Lange, F.F., Infiltration of porous alumina bodies with solution precursors strengthening via compositional grading, grain size control, and transformation toughening, J. Am. Ceram. Soc., 79(7), 1810-1814, 1996. 

The three principle methods of strengthening materials are grain-size reduction, solid-solution strengthening, and plastic-deformation processes, like strain (work) hardening. 

With respect to the ratio of components and their grain sizes, the mixtures should be composed in order to allow good forming, to bring about strengthening and densification by subsequent firing, and to produce the required phase composition of the product. 

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