Universal Maximum Strength of Solid Metals and Alloys

Interstitial electron density rho o is offered as a direct metric for maximum strength in metals, arising from universal properties derived from an electron gas. rho o sets the exchange-correlation parameter rs in density -functional theory. It holds also for maximum shear strength tau max in polycrystals [M. Chandross and N. Argibay, Phys. Rev. Lett. 124, 125501 (2020)]. Elastic moduli and tau max for polycrystalline (amorphous) metals are linear with rho o and melting Tm (glass-transition Tg) temperature. rho o or rs, even with rule-of -mixture estimate, predicts relative strength for rapid, reliable selection of high-strength alloys with ductility, as confirmed for elements to steels to complex solid solutions, and validated experimentally.

Automated summary

Interstitial electron density rho o is a universal metric for strength in metals, and sets the exchange-correlation parameter rs in density-functional theory. It also predicts maximum shear strength tau max and linear relationships between elastic moduli and rho o, as well as between tau max and melting/glass-transition temperature. This prediction allows for rapid and reliable selection of high-strength alloys with ductility, as demonstrated for various types of metals and validated experimentally.