Influence of average radii of RE ³⁺ ions on phase structures and thermal expansion coefficients of high-entropy pyrosilicates

High-entropy pyrosilicate element selection is relatively blind, and the thermal expansion coefficient (CTE) of traditional ?-type not adjustable, making it difficult to meet requirements various types ceramic matrix composites (CMCs). The following study aimed develop a universal rule for high-entropy achieve directional control pyrosilicate. current investigates design method obtaining pyrosilicates with stable ?-phase ?-phase by introducing rare-earth (RE) cations. solid-phase was used create 12 different 4–6 components. gradually transformed from an increase in average radius RE3+ ions ( r¯(RE3+)). nine small id="MA2">) preserve or stability at room temperature maximum 1400 ?. intrinsic relationship between coefficient, phase structure, RE–O bond length has also been found. This provides theoretical background designing perspective id="MA3">). guidance makes easier synthesize use environmental barrier coatings (EBCs). ?-type can be altered through component match CMCs.