To improve yield, to suppress the increase in cost, and to increase the degree of freedom of selecting a matrix by including a reinforced fiber body in which a plurality of reinforcing fibers are arranged substantially parallel to each other, and metal foils joined with this reinforced fiber body.

Two Ti alloy foils 5 are arranged oppositely to each other on a preliminarily formed recessed part side, and reinforcing fibers 3a are held between the Ti alloy foils 5. Both the foils and the reinforcing fibers are inserted between surface plates 11. Both of them are hot-pressed while heated in vacuum by a heater 13. The pressing pressure is about 1-10 MPa, and the heating temperature is about 700-1,200°C. Metal atoms are diffused between the reinforcing fiber body 3a and the Ti alloy foils 5, and a super-plastic phenomenon is generated under the heating temperature to firmly join both of them. After pressing them for a specified time, the surface plates 11 are opened, a mono-tape preform 50 which is a composite material of both of them is obtained, and coiled by a coiling roller 15.