Effects of grain size on the microstructure and texture of cold-rolled Ta-2.5W alloy

The effect of grain size on the texture and deformation microstructure of cold-rolled Ta-2.5W alloy has been investigated. The alloy with fine grains has higher microhardness than that with coarse grains under the same cold-rolling conditions. Microbands are developed when the cold-rolled reduction reach 20% and the density of microbands increases with increasing reduction. The boundaries of microbands consist of cross dislocation network when cold-rolled by 40%. Meanwhile, mature α and γ fibers are developed in these two alloys. Compared the alloy with coarse grains, the alloy with fine grains has a stronger texture intensity of γ fiber, which is mainly composed of microbands. Meanwhile, the average space between boundaries of microbands is smaller than that in alloy with coarse grains. The effect of subgrain strengthening and texture strengthening in fine-grain alloy is greater than those in coarse-grain alloy.