BIMETALLIC THIN STRIP AND ITS PRODUCTION METHOD Russian patent published in 2017 - IPC B32B15/20 B23K20/04 B23K103/08 

FIELD: metallurgy.

SUBSTANCE: bimetallic strip contains an aluminum-based primary layer in the annealed condition and at least one copper-based cladding layer in the annealed condition. The ratio of the ultimate strength values of the cladding layer and the primary layer is greater than 1, and the ratio of the thickness values of the cladding layer and the primary layer is defined by the following condition: N_cl/N_pl<0.2235(σ_cl/σ_pl)^-0.628, where N_cl, H_pl are thicknesses of the cladding layer and the primary layer in mm; σ_cl, σ_pl is the tensile strength of the cladding layer and the primary layer in MPa. During manufacturing of bimetallic strips joint rolling of prepared layers, diffusion annealing, cold post-rolling followed by annealing are performed. Diffusion annealing is carried out when the total deformation determined by the following condition is achieved: E=-0.0543(N_cl/N_pl)²+2.5686(N_cl/N_pl)+49.4, where E is the total deformation of the tape from the initial state. Each subsequent annealing is carried out when the total deformation determined by the following condition is achieved: E≤-0.23(N_cl/N_pl)²+9.8(N_cl/N_pl)-11.2.

EFFECT: no ruptures in cladding tapes and, as a consequence, an increased product yield.

2 cl, 2 dwg, 1 tbl