ABSTRACT
A s with cold deformation, hot deformation is accompanied by damage to the crystal lattice
within grains of M g solid solution. A s imperfections arise, they destroy the arrangement of
the precipitates formed during solid solution decomposition. The places within grains
where the imperfections are concentrated become favoured for precipitates. The next two
micrographs show typical examples of solid solution decomposition in hot deformed M g
alloys. Figure 102e demonstrates preferable precipitation along the sliding bands within the
primary grain of M g solid solution along with grain boundaries. The sliding bands form
after hot deformation and divide the grain into few pieces. Figure 102f demonstrates
Gd-r ich particles precipitated in hot deformed M g - G d alloy. Directions of the plate-like
particles change within the grain following misorientation of the separate grain parts
Figure 102. Light micrographs of the M g - R E alloys, a - M g - 3 mass % Nd, deformed 80% at 350°C, x 1000, b - Mg-13.6 mass % Gd, deformed 40% at 400°C, x240, c - Mg-2 .2 mass % Y, deformed 40% at 450°C, x 240, d - Mg-19.1 mass % Dy, deformed 40% at 500°C, x 250, e - Mg-19.1 mass % Dy, deformed 40% at 350°C, x 1000, f - Mg-21.5 mass % Gd, deformed at 400°C, x 1000.