Superalloy liquid interface diffusion bonding

Abstract

A liquid interface diffusion process is provided where a thin deposit (from 1/2 to 4 mils) of nickel (and/or cobalt) having 4-12 weight percent boron is plated on the nickel or cobalt based alloy faying surfaces. In the case of honeycomb sandwich, the plating is applied to the edge of the core or on the facing sheets and the assembly held together in intimate contact and exposed to a temperature sufficient to cause the Ni-B eutectic to melt. At the eutectic temperature a liquid is formed which makes a metallurgical joint. Upon further time at temperature the boron is diffused into the substrate so that isothermal solidification occurs and the boron is diluted to a small concentration. Sufficient time is allowed (on the order of one or more hours) so that the melting point at the joint area is essentially the same as the substrate and the joint is comparable to a diffusion bond. In the case of solid sections the Ni(Co), 4-12% B plating is deposited on one faying surface or 1/2 the amount on both faying surfaces and exposed to the same conditions as described above.

Dependencies are inferred from the claim text.