Brazing technology
OwnerSuri A. Sastriinventor
Life of this patent
Estimating the term…
Loading patent…
OwnerSuri A. Sastriinventor
Estimating the term…
A method of braze joining a copper member to a substrate of metal or ceramic material is disclosed according to which a diffusion barrier coating as defined is applied to the substrate alone, and a selected brazing alloy is interposed between copper member and substrate, followed by a two-step heating treatment. In the first step the assembly is heated at a temperature and for a time sufficient to melt the brazing alloy and cause a bond to form between the brazing alloy and the copper member and between the brazing alloy and the substrate. In the second step the temperature is raised and maintained in the range from about 600.degree. C. to about 950.degree. C. in a "solutionizing heat treatment" (as defined) for a time sufficient to allow the brazing alloy to form an "extended solid solution" (as defined) with copper in a controlled fashion to convert the bond to a strong joint which is resistant to thermal stress.
A method of braze joining a copper member to a substrate of metal or ceramic, comprising the steps of applying an adherent, non-reactive diffusion barrier coating to said substrate, interposing a brazing alloy between said copper member and said diffusion barrier coating, said brazing alloy in molten form being capable of wetting said diffusion barrier coating, first heating to a temperature and for a time sufficient to liquefy said brazing alloy and form a bond between said brazing alloy and said copper member and between said brazing alloy and said diffusion barrier coating, and further heating at a temperature from about 600.degree. C. to about 950.degree. C. for a time sufficient to allow said brazing alloy to form an extended solid solution with copper from said copper member and thereby convert said bond to a strong joint which is resistant to thermal stress.
Dependencies are inferred from the claim text.