ABSTRACT
A special precise technique was used for registration of the X-ray reflexes aiming to
provide more reliable data. Nevertheless, no visible extension of the L a solubility in solid
M g was established in the experiments after rapid solidification as compared with
solidification in normal conditions at 10 1 K/s . Investigation of the rapidly solidified alloys
using transmission electron microscopy and electron diffraction [249] showed that the
M g - L a compound visible in the structure had a hexagonal crystal lattice. Its parameters
were a = 1.178 nm and c - 1.020 nm. These values were close to those of the equilibrium
phase M g 1 7 L a 2 , but a few additional reflexes in the electron patterns indicated that the
lattice of the M g - L a compound in the rapidly solidified alloys differed from that of
M g 1 7 L a 2 . The M g - L a compound in the rapidly solidified alloys did not coincide, either,
with the other equilibrium phase M g 1 2 L a established in the M g - r i c h M g - L a alloys because
the lattice of the latter was of the orthorhombic type.
