PURPOSE: To obtain a composite blank material which can be easily produced and has good strength and durability by using Ti or Ti alloy as a core material, cladding an alloy contg. a prescribed amount of Pd, Si, Ga and Ag as an intermediate material thereon and cladding a corrosion resistant material on the outside thereof.

CONSTITUTION: This composite blank material is formed by using a the Ti or Ti alloy as the core material 1, cladding an Ag alloy contg. 2.5W50wt% Pd and 0.01W10wt% 1 or two kinds of Si and Ga as the intermediate layer 7 on the outside of the core material and cladding the material 2 having the good corrosion resistance and brazing characteristic, for example, any of Ni-Cr alloy, Ni-Cu alloy, Au alloy, Ag alloy and stainless steel to the outside thereof. The Ag alloy used for the layer 7 acts to relieve the thermal strain in the stage of brazing and the Pd acts to prevent the exfoliation after brazing. The Si and Ga has the effect to prevent the abnormal growth of the Pd-Ti layer and the consequent generation of exfoliation when the brazing temp. is increased too much.