Substitution of vanadium for copper in the (Bi, Pb)₂Sr₂Ca₂Cu₃O_10+σ system

X‐ray powder diffraction, ac magnetic susceptibility, electrical resistivity measurements, and scanning electron microscopy are used to investigate the effect of V substitution in the Bi_1.6Pb_0.4Sr₂Ca₂‐Cu_3–xV_xO_y system for different values of V concentration x (0 ≦ x ≦ 0.5). The addition of V is found to lower the melting point of the system. The samples become multiphasic compounds including the 2223 phase, the 2212 phase, the 2201 phase, and other non‐superconducting phases with increasing x. The lattice parameter c of the 2223 phase decreases from 3.676 to 3.672 nm. There exists an extra step of diamagnetic transition in ac susceptibility curves at lower temperatures (above 77 K) for the samples, which is mainly caused by weak links consisting of non‐superconducting phases and higher‐angle boundaries between the superconducting grains. The transition temperature of the 2223 phase monotonously decreases by 3.4 K with the substitution of V for Cu. The suppression of T_c may be related to a decrease of the hole concentration, which can be caused by Cu vacancies in the CuO₂ planes.