The trade-off between strength and corrosion resistance is an important challenge facing aluminum alloys. Here, we report the design of aluminum composite alloy combining novel corrosion resistant strain-hardening alloy and T-phase precipitation-hardened alloy prepared by hot rolling. Good metallurgical bonding is achieved due to the uniform gradient diffusion of the elements near the bonding interface. We find that the strong strain field in the diffusion layer resulted in semi-coherent precipitates compared with the single alloy. The discontinuous distribution of the grain boundary precipitates and the absence of precipitation free zone contribute to the improved corrosion resistance of the coating alloy on each side. The composite achieves 502 MPa tensile strength, 400 MPa yield strength, 10% elongation, and superior corrosion resistance, surpassing conventional aluminum alloys in overall performance.
Wang et al. (Tue,) studied this question.