Method of high temperature assembly

In a fluxless method of high-temperature assembly or brazing, of similar or different, metallic, nonmetallic or partially metallic components by means of bonding with an added metal or alloy with a melting point below that of the most fusible component without mechanical or chemical preparation of the surfaces of the components at the areas to be bonded to remove oxide contaminants, the improvement comprising effecting assembly by the successive steps of:

• a. positioning the components in an assembled relationship with the metal or alloy to be added immediately adjacent areas of the components where bonds are to be formed;
• b. positioning the assembly of (a) in a chamber and establishing a residual pressure of below about 1 torr;
• c. heating the assembly of (b), while maintaining the residual pressure below about 1 torr, to brazing temperature at least equal to a temperature required to melt the added metal or alloy in the presence of one or more halogens derived from one or more halogens in a free or combined state utilized in a manner so as to only exert a partial pressure that does not interfere with maintaining said residual pressure below about 1 torr to eliminate any surface film of oxide on the components to be bonded;
• d. subjecting the assembly of (c), while maintaining the residual pressure below about 1 torr, to the brazing temperature, above about 800.degree. C, while maintaining the residual pressure below about 1 torr, for a sufficient time for the added metal or alloy to substantially fill the areas where bonds are to be formed without appreciable spread of the bonding metal or alloy over surfaces of the components in areas not to be bonded and without significant halogen contamination of the components in areas not to be bonded;
• and
• e. cooling the bonded assembly to ambient temperature.