New method to diffusion bond superalloys

Abstract

A new method for diffusion bonding nickel base and cobalt base superalloys has been developed, which is based on non-chemical oxide removal before the bonding process. Using this method, diffusion bonds were produced in nickel base and cobalt base superalloys with ‘virtually invisible’ bond interfaces and compositions very close to the bulk alloys. The bonding time required is about 1 h and the results of severe mechanical tests of the bonded samples, including directionally solidified (DS), single crystal and dissimilar superalloys, are very promising. The new oxide removal method is very rapid, does not require the use of any sophisticated equipment and is not a costly process. The high temperature properties of bonded samples are currently being investigated. European and USA patents have been applied for and the details of this new method are to be published in the future.