Deep-Drawing of Commercially-Pure Niobium Sheet

Pure Niobium is a material of interest for high-energy-physics applications including superconducting accelerators. Cold-rolled sheets Nb exhibit significant plastic anisotropy. Here we report on the mechanical and forming properties 99.95% pure, 1.02 mm thin, cold-rolled sheet. Uniaxial tension, biaxial tension disc compression experiments are performed, first two at multiple angles to rolling direction The very ductile (uniform elongation ~30%), exhibits anisotropy (e.g., R-values range from 1.2 in 45 o 2.5 90 ). results used calibrate Yld2000-2D anisotropic yield function, with an exponent 6 as BCC. They also extract hardening curve beyond limit load uniaxial tension. Deep-drawing performed using die 27.6 dia. punch 25.4 Blanks various diameters used. successfully drawn cups earing. simulated Abaqus/Standard shell elements. It shown that properly calibrated model enables numerical simulations match experiments.