The need to produce oxidation- and corrosion-resistant joints for service at high temperatures, and the need to develop brazing filler metals that are compatible with the base metals used to obtain maximum performance under these conditions, has prompted extensive research by many organizations. As a result of this research, a whole new industry has been created. Much of the impetus behind these efforts is associated with the joint requirements of the aerospace, jet engine, and nuclear industries. Like other metal-joining processes, brazing was long considered to be more an art than a science. The research on high-temperature brazing has done much to dispel this belief.
Before discussing high-temperature brazing as a separate entity, it is well to reflect on the general attributes of the brazing process. Brazing is a process that is well suited to mass-production operations where many parts must be joined simultaneously or where large, complex assemblies must be joined in a single operation. Brazing is often the only practical method to assemble parts whose dimensions, design, or materials of construction preclude joining by fusion-welding methods.