DISPERSION-STRENGTHENED NICKEL
NICKEL AND NICKEL-CHROMIUM alloys can be strengthened to very high strength levels by the uniform dispersion of very fine refractory oxide (Tho,) particles throughout the alloy matrix. This is done using powder metallurgy techniques during manufacture of the alloy. When these metals are fusion welded, the oxide particles agglomerate during solidification. This destroys the original strengthening afforded by dispersion within the matrix. The weld metal will be significantly weaker than the base metal. The high strength of these base metals can be retained with processes that do not involve melting the base metal. Contact the base metal supplier for current recommendations for specific conditions.