Anisotropy in tensile properties of ITER-conformant and cross-rolled tungsten grades

This study experimentally investigates the tensile properties of five tungsten grades for fusion applications at temperatures of 300 ◦C, 500 ◦C, and 800 ◦C, focusing on the influence of microstructural characteristics such as texture, grain shape aspect ratio, and grain boundary density. Texture analysis based on electron backscatter diffraction highlights diverse components in all tungsten grades. The Taylor factor and strength anisotropy variations suggest that texture is not the sole determinant of strength. Grain shape aspect ratio (short-to-long axis ratio) affects strength anisotropy, increasing at 300 ◦C and decreasing at 500 ◦C, converging at 800 ◦C. The anisotropy of uniform elongation and post-necking toughness decreases with grain shape aspect ratio at 300 ◦C, transitioning at 500 ◦C, and nearly disappears at 800 ◦C. Yield strength correlates with high-angle grain boundary density at 300 ◦C and 500 ◦C, which indicates that dislocation-grain boundary interaction is a ther­mally activated process in this temperature range.