Today's Industrial Products and Solutions March 2019 | Page 13

Perfecting
Diffusion
Bonding
Specialized furnaces with integrated press-
es provide superior control of pressure and
temperature to create better diffusion bonds
when joining similar or dissimilar metals
For many years, diffusion bonding has been
utilized to join high strength and refractory
metals that are either difficult or impossible
to weld by other means. The process, which
involves applying high temperature and
pressure to similar or dissimilar metals mat-
ed together in a hot press, causes the atoms
on solid metallic surfaces to intersperse and
bond.
Unlike traditional brazing techniques, the
resulting bond exhibits the strength and
temperature-resistance of the base metals.
It also eliminates the need for filler material
that affects the final weight and dimensions
of the mated metals.
Despite its benefits, the use of diffusion
bonding has been limited by more practical
considerations. Specifically, the size limita-
tion of the furnace chamber as well as limits
to the amount, and uniformity, of the pres-
sure applied across the entire surface area
of the part. Run times are also long, often