The interface is pivotal to the deformation behavior of heterogeneous laminates, yet traditional stationary interfaces suffer from stress concentration and inadequate strength in the interface affected zone (IAZ), severely limiting laminate performance. Herein, we propose an innovative “cold spraying interlayer + roll-bonding” (CSIR) process to fabricate magnesium/aluminum (Mg/Al) laminates with simultaneously enhanced interfacial strength and toughness. The average interfacial shear strength reaches 113.6 MPa, nearly doubling the ∼60 MPa of traditional processes. This exceptional performance originates from three core factors: a microscopic three-dimensional (3D) non-stationary interface, sufficient atomic diffusion in the IAZ, and a heterogeneous lamellar transition layer. The high-velocity impact of cold sprayed Al-Al 2 O 3 hybrid particles constructs a microscopic 3D interface between substrates and coating, expanding the bonding area and promoting the diffusion of atoms in the IAZ. The transition layer features low porosity and a tri-modal structure (discrete hard Al₂O₃ particles, strong Al nanograins, ductile coarse Al laths with small-angle grain boundaries). Here, equiaxed fine intermetallic compound grains surround the coarse Al laths, Al nanograins form around Al₂O₃ particles, and this structure enhances strain delocalization. The CSIR process enables large-scale, low-cost fabrication of heterogeneous lamellar transitional structures, offering a novel strategy for high-performance Mg/Al laminates.
Ma et al. (Fri,) studied this question.