Making an Ultra‐Ductile Laminate Medium Entropy Alloy by Pressure Thermal Treatment

Abstract Innovations in either high‐performance materials or microstructures by conventional processing methods are often challenging to achieve without a synergistic combination. The perfect combination of pressure and temperature offers a great prospect for altering the microstructure that would permit achieving the extreme properties in functional and structural materials. Here, pressure thermal treatment is used to make a laminate medium‐entropy alloy that exhibits a combination of a large fracture elongation of ≈122 percent and a high fracture strength of ≈900 megapascals. The high tensile ductility stems from the strong synergistic effects of the laminate structures with low‐energy interfaces. Consequently, versatile dislocation configurations and deformation twinning are sequentially stimulated, effectively improving the alloy's ability to accommodate plastic deformation. This unique laminate structure with the low‐energy interface obtained from pressure thermal treatment offers a paradigm for developing hierarchically metallic materials with exceptional mechanical properties.