INTERDIFFUSION STUDY IN THE Nb-Si BINARY SYSTEM

Diffusion experiments on Nb/Si couples were conducted at 1050°C, 1150°C, 1250°C for annealing for 8h, 10h and 15h. Two intermediate phases, NbSi2 and Nb5Si3, were found to develop and grow as parallel layers in the Nb/Si couples, according to the parabolic rate law. The diffusion properties of the different phases were evaluated in terms of alternative theories, which were demonstrated to be equivalent algebraically but complementary because they are expressed in terms of different experimental variables.