Method of manufacturing a clad material of bronze alloy and steel

A manufacturing method of a clad material composed of a bronze alloy and a steel is provided, including: scattering a bronze alloy powder on a steel back metal; sintering the bronze alloy powder to obtain a bilayer material having a porous bronze alloy layer on the steel; dry-rolling and a sintering the bilayer material so that the bronze alloy layer has a porosity of 3% or less; and wet-rolling the bilayer material with supplying a rolling oil to surfaces of rolling rolls. The clad manufactured according to this method can be heat-treated without an disadvantage in a conventional wet-rolling that entering rolling oil vaporizes in the bronze alloy layer during the heat treatment to form new voids. Therefore, it becomes possible to make a bronze alloy layer high in density in small times of rolling, thus enabling an increase in production efficiency.