Tailoring strength-ductility synergy of Al/Ti laminates by thickness ratio optimization and asymmetric cryorolling

Al/Ti laminated strips with thickness ratios of Al:Ti = 1.6:1 and 2:1 were prepared via hot rolling and subsequently processed by room-temperature rolling (RTR) and asymmetric cryorolling (ACR). The results reveal that ACR-processed strips exhibit enhanced strength while retaining comparable elongation relative to RTR laminates. Notably, laminates with the 1.6:1 thickness ratio show superior mechanical properties under both processing routes, especially after ACR, reaching values of 432 MPa in tensile strength and 8.1% in elongation. Microstructural analyses ascribe the performance enhancement to ACR-induced improvements in interlayer deformation coordination, elevated dislocation density, and an increased fraction of low-angle grain boundaries. Digital image correlation investigations further demonstrate that 1.6:1 thickness ratio laminates develop an extended interface-affected zone and pronounced strain gradient during tensile deformation, which collectively enhance strain hardening capacity and contribute to their superior comprehensive mechanical properties. These findings underscore the synergistic effects of thickness ratio optimization and ACR-induced microstructural refinement in tailoring the performance of Al/Ti laminates.