A Kinetic Study of Order-Disorder Transition in Ni–Cr Based Alloys

Comprehensive Analysis of Ordering in CoCrNi and CrNi2 Alloys

“…5b), we focused on samples that represent the extremes of ordering. The aged CrNi2 alloy displayed significant enhancements in ultimate tensile strength (𝜎 𝑈𝑇𝑆 ) and yield strength (𝜎 0.2 ) after 240 h aging, a state characterized by the formation of ordered oI6 precipitates, as established previously 22,23,31 . Notably, the ductility, measured as strain to failure (εf), did not show marked changes.…”

“…To overcome these gaps, the primary objective of this research is to establish a new approach to experimentally quantify the presence and type of CSRO, and to propose a mechanism by which CSRO can form and be destroyed. To do so, we chose to work with CoCrNi, since it is the most widely studied composition on this topic, together with the model binary CrNi2 (Cr33Ni66 in at.%), which was selected due to the similarity with the ternary alloy and the large body of work on this composition and its ordering reactions 19,[21][22][23] . These compositions were produced and thermomechanically processed as described in Methods; the resulting material was cut into samples that were annealed at 1273 K for 1h and water quenched, producing a recrystallized microstructure.…”

“…The samples were then aged at 748 K for different times up to 240 h followed by water quenching. The temperature used in the aging treatments was selected based on B. Stephan et al 22 work, which indicates that 748 K is the temperature that provides the maximum transformation kinetics in CrNi2 for the formation of the ordered oI6-CrNi2 phase (Immm space group).…”

Modeling and Simulation of Microstructure Evolution and Deformation in an Irradiated Environment

“…Many research groups have thus selected model binary alloys, which form the LRO precipitates after reasonable aging times [113,183,200,172]. These studies connect the formation of LRO Ni 2 Cr precipitates with increased hardness of the model alloy.…”

“…The 10,000 hours of thermal aging were selected to ensure the formation of a stable LRO precipitation population [183]. Because of the difficulties with measuring the diameter of the coherent LRO precipitates [181], many of these studies rely on measurements of lattice contraction to determine if LRO precipitates have formed [172]. Thus only a few studies provide experimental measurements of LRO precipitate diameter, and the potential for experimental error is high [181].…”