A number of new Bi m+1Fe m-3Ti 3O 3m+3 compounds with integer and fractional m values are identified in the Bi 4Ti 3O 12-BiFeO 3 system. All of the compounds are shown to have Aurivillius-type structures. The phase-transition and decomposition temperatures of the new and earlier known compounds of the Bi 4Ti 3O 12-BiFeO 3 system are determined. The linear thermal expansion coefficients of the synthesized compounds are evaluated using dilatometry, and their sintering onset temperatures are determined.