Abstract
A study of precipitate phases in an Al−Zn−Mg alloy in the T74 condition has been conducted by means of high resolution electron microscopy. It has been observed that G.P. zones, η′ and η phases exist simultaneously in the matrix. The G.P. zones are plate-like forming on (111) matrix plane. The η′ phase has a hexagonal structure witha=0.496 nm,c=1.403 nm and the orientation relationship with the matrix is\((001)_{\eta '} //(1\overline {11} )_{m,} [120]_{n'} //[110]_m \). A new orientation relationship between the η phase and the matrix is found to be\((001)_\eta //(1\overline {11} )_{m,} [\bar 110]_n //[110]_m \).
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Jiao, H., Li, C. The HREM study of precipitates in an Al−Zn−Mg alloy. Adv Perform Mater 2, 305–309 (1995). https://doi.org/10.1007/BF00705453
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DOI: https://doi.org/10.1007/BF00705453