Hyper-Range Amorphization Unlocks Superior Damage Tolerance in Alloys
摘要
Shear bands dictate the failure mechanisms of alloys across various strain rates and limit the damage tolerance of the alloy. While short-range amorphization has the potential to mitigate shear effects, it has thus far been confined to the nanoscale. Here, we extend amorphization to the micrometer scale, fundamentally replacing shear-dominated failure in multi-principal element alloy micropillars. We implement continuous compression strain-training from low to high strain rates, generating a top-down high-density dislocation gradient that drives the formation of a topological disorder network, extending over one-third of the micropillar height, which we define as hyper-range amorphization. Within the amorphous bands, atoms exhibit dynamic disorder, and the lattice rearranges and recovers, dissipating shear stress. The alloy achieves an ultimate compressive strength of ceramic level ( ~ 6.5 GPa), while maintaining ~59.1% plasticity. This work reveals a strain engineering-based mechanical mechanism for extending amorphization, establishing it as a viable pathway to enhancing the structural stability and energy dissipation capacity of alloys.