Exploration of spinodal decomposition in multi-principal element alloys (MPEAs) using CALPHAD modeling

Accelerated exploration of multi-principal element alloys with solid solution phases

Recent multi-principal element, high entropy alloy (HEA) development strategies vastly expand the number of candidate alloy systems, but also pose a new challenge--how to rapidly screen thousands of candidate alloy systems for targeted properties. Here we develop a new approach to rapidly assess structural metals by combining calculated phase diagrams with simple rules based on the phases prese...

Atomic Structure Modeling of Multi-Principal-Element Alloys by the Principle of Maximum Entropy

Atomic structure models of multi-principal-element alloys (or high-entropy alloys) composed of four to eight componential elements in both BCC and FCC lattice structures are built according to the principle of maximum entropy. With the concept of entropic force, the maximum-entropy configurations of these phases are generated through the use of Monte Carlo computer simulation. The efficiency of...

Spinodal decomposition in microemulsions

Direct observation of spinodal decomposition phenomena in InAlN alloys during in-situ STEM heating

The spinodal decomposition and thermal stability of thin In0.72Al0.28N layers and In0.72Al0.28N/AlN superlattices with AlN(0001) templates on Al2O3(0001) substrates was investigated by in-situ heating up to 900 °C. The thermally activated structural and chemical evolution was investigated in both plan-view and cross-sectional geometries by scanning transmission electron microscopy in combinatio...

Monte-Carlo simulations of spinodal ordering and decomposition in compositionally modulated alloys

The early-stage kinetics of interdiffusion in compositionally modulated films have been studied by Monte-Carlo simulations on an Ising lattice in two and three dimensions, using nearest-neighbor interactions. For a negative heat of mixing and below the order-disorder transition temperature, if a short-wavelength modulation is along a direction that is not consistent with long-range order, then ...