Interfacial behavior of brazed Cu-Zn filler subjected to electromagnetic coupled cryogenic treatment

•A new electromagnetic coupled cryogenic treatment was applied to Cu-Zn interface.•The shear strength of the treated Cu-Zn filler interface increased by 35.2 %.•The treatment relieved the residual tensile stress of the Cu-Zn interface.•The dendrites and finer α-Cu(s.s), and soft β-Cu(s.s) increased shear strength.