Precipitation-Modulated Harmonic Architectures Enable Superior Strength-Ductility Synergy from Cryogenic to Elevated...

High-performance materials that exhibit a robust strength-ductility synergy across cryogenic to high temperatures are essential for aerospace applications, yet achieving this combination remains a significant challenge in materials development. Here, we report that remarkable mechanical properties across a broad temperature range can be achieved in bimodal harmonic-architectured (BHA) alloys. In this architecture, spherical precipitates stabilize coarse-grained cores, while lamellar precipitates facilitate selective recrystallization, resulting in a reproducible necklace-like topology. This engineered microstructure delivers exceptional mechanical performance from -196 °C to 700 °C, consistently achieving yield strengths of 1-2 GPa and ductilities exceeding 10% throughout the entire temperature spectrum. Quantitative analysis reveals that precipitation and grain-boundary strengthening are the primary contributors to strength at all temperatures, whereas the contribution of dislocation hardening decreases progressively with increasing temperature. The deformation mechanisms exhibit temperature-adaptive cooperation: dislocation forests and nanotwins enhance deformation at cryogenic temperatures, dislocation-precipitate interactions dominate plasticity at ambient conditions, and interfacial back-stress accommodation ensures coordinated deformation of bimodal grains at elevated temperatures. This adaptive synergy effectively suppresses both cryogenic embrittlement and high-temperature softening, establishing a robust structural foundation for broad service applicability. The BHA engineering offers a versatile pathway for developing next-generation alloys with superior properties required for wide-temperature applications.