High temperature X-ray diffraction study of phase decomposition in rapidly quenched Al-Ge-Si

The phase decomposition occurring during the heating of rapidly quenched Al-Ge-Si alloys has been investigated in situ by means of synchrotron radiation X-ray diffraction. The metastable Al-Ge phases formed in the as-quenched state transform during heating to Al and Ge. The addition of silicon decreases the transformation temperature. A Ge(Si) solid solution is indicated by a systematic change in the lattice constant of Ge as a result of the diffusion of Si from the Al matrix into the phase-separated Ge matrix.