Architecting multiscale heterostructure for exceptional strength-ductility synergy in super duplex stainless steel 2507

A multiscale heterostructure integrating duplex phases, grain size contrast and nanoscale chemical modulations were architected in super duplex stainless steel 2507, achieving a high yield strength of 1112 MPa and ultimate tensile strength of 1411 MPa with a large elongation of 27%. The primary strengthening mechanisms are HDI, dislocation and spinodal decomposition strengthening which were quantitatively assessed. A predictive model for the yield strength evolution with aging time was developed. This study demonstrates a novel strategy for developing high-performance alloys through leveraging multiscale heterostructures to overcome the strength-ductility trade-off.