Particle Redistribution and Grain Refinement during Processing by Hydrostatic Extrusion
In this study particle redistribution and grain size refinement induced by hydrostatic extrusion (HE) have been studied in two Al-Si cast alloys (Al-9%Si and Al-11%Si). It has been found that HE results in a significant changes in particle shape, size and distribution which was revealed by SEM observations and quantified using stereological parameters. At the same time, significant grain refinement down to ~100 nm in diameter takes place in aluminium phase. Such a microstructure evolution affects substantially the mechanical properties of two-phase alloys. The yield strength and tensile strength increase over two times whereas the plasticity only slightly decreases.
Yuri Estrin and Hans Jürgen Maier
K. Wawer et al., "Particle Redistribution and Grain Refinement during Processing by Hydrostatic Extrusion", Materials Science Forum, Vols. 584-586, pp. 541-546, 2008