Verma, A.; Singh, J.B.; Sundararaman, M.; Wanderka, N.: Resistivity and Transmission Electron Microscopy Investigations of Ordering Transformation in Stoichiometric Ni2(Cr0.5Mo0.5) Alloy. Metallurgical and Materials Transactions A 43A (2012), p. 3078-3085
The evolution of long-range order (LRO) from short-range order (SRO) and vice versa was studied by combining resistivity measurement and transmission electron microscopy (TEM) investigations on solution-treated samples of composition Ni2(Cr0.5Mo0.5). The progress of microstructural evolution during the isochronal run for the resistivity measurement was followed. The measured variation in the intensity of superlattice spots during SRO to LRO transition was correlated with the resistivity profile obtained during the isochronal run. The reappearance of SRO was observed after the disappearance of LRO. The isothermal transformation temperature for the appearance of the long-range ordered state, the beginning of disappearance of the long-range ordered state, and the reappearance of the short-range ordered state in the solution-treated sample were determined from the resistivity curves obtained for different heating rates. The resistivity profile was qualitatively explained on the basis of ordering and clustering of solute atoms associated with the formation of different ordered phases obtained from microscopic evidence.