Interface-correlated deformation behavior of a stainless steel-Al-Mg 3-ply composite

► Annealing time is a key factor to generate distinctive layers at Mg-Al interface. ► Rapid hardening of β (Mg2Al3) phase takes place upon increasing annealing time. ► Uniaxial tensile test for a STS-Al-Mg 3-ply sheet results in interface hardening. ► Interface crack propagation by bending indicates the embrittlement of β phase.