Multiferroic ceramics of 0.705BiFeO(3) - 0.275BaTiO(3) - 0.02Bi(0.5)Na(0.5)TiO(3)+ 1 mol% MnO2 were prepared by a conventional ceramic technique and the effects of sintering temperature (T-s) and dwell time (t(s)) on the phase structure, piezoelectric and multiferroic properties of the ceramics were investigated. As Ts increases from 880 degrees C to 1040 degrees C, the ceramics are transformed from rhombohedral to tetragonal structure and a MPB is formed at T-s =1000 degrees C and t(s) = 2 h. The increase in T-s greatly improves the densification, electric insulation, ferroelectricity and piezoelectricity of the ceramics, while relatively weak dependences on t(s) are observed. As T-s increases from 880 degrees C to 1000 degrees C, the magnetism of the ceramics is significantly enhanced and the values of M-r are increased by similar to 400%. The optimum sintering conditions of the ceramic is 1000 degrees C/2 h, in which high density, good electric insulation and enhanced ferroelectricity (P-r= 18.4 mu C/cm(2)), piezoelectricity (d(33) = 140 pC/N, k(p) = 31.4%) and ferromagnetism (M-r = 0.099 emu/g) are simultaneously obtained. (C) 2015 Elsevier Ltd. All rights reserved.