PURPOSE: To enable the simple and sure bonding without elution of braze material on faying surfaces and impairment of appearance by providing the bonding braze material layer of a melting point lower than base metal on part or the entire part of at least one surface of corrosion resistant alloy material.

CONSTITUTION: Bonding braze material layer of a melting point lower than that of corrosion-resistant alloy material is clad on part or over the entire part of one surface of the alloy material. For example, this clad material is used for hinge parts 13, 13' and it is cut to blank size and finished to the hinge shape while the flatness of the clad surface is held maintained. Thence, the surface to be bonded are cleaned together with temples 11, 12 and hinges 13, 13', after which the hinge 13 is fixed to the temple 11 and the hinge 13' to the temple 12. After these are fixed, the hinge bonded portion is heated in the atmosphere or a neutral atmosphere and is then cooled, whereby the hinge parts may be formed to the temple parts within a short time.