Figure 1 Metallographs for as annealed Mo in (a), Mo-5Re in (b), Mo-14Re
in (c) and Mo-42Re in (d).
As shown in Figure 2a and 2b, the orientation in red grains is
[100], in green grains is [110]. Grain with 111 orientation is
rarely observed in Mo-14Re and Mo-42Re, meaning textures form during
thermal extrusion. The grain size in Mo-42Re is much smaller than in
Mo-14Re, suggesting evident grain-fining effect of Re in Mo alloys.
Irregular grain boundaries verify that no obvious crystallization
occurs. The inserts in Figure 2 show the micrographs of pillar with
diameter 2μm and height 4μm.