Patent ID: 8083124
Filing Date: 2011-12-27
Classification: B23K,C22C,C22F,C30B,F01D,F05D

Abstract:
1. A method of joining a plurality of single crystal members with a juncture between them, including selecting the members to have, at the juncture, a crystal orientation mismatch of less than about 5° therebetween, the members further having substantially the same gamma prime solution temperature range, incipient melting temperature range, and having related compositions, with the members being placed in juxtaposition with a bonding foil disposed at the juncture therebetween, with each member in contact with the foil to provide an assembly, comprising the steps of: a) providing the bonding foil with a composition matched with the composition of the members except for a lower content of gamma prime formers, so that a significantly lower gamma prime content in the foil increases foil ductility, the foil b) bonding the assembly by heating the assembly to the second temperature; and c) holding the assembly at the second temperature for at least 10 hours, sufficient to enable the members at the juncture to act as single crystal seeds, to progressively grow epitaxially into the foil to form a joint region, and thereafter to chemically homogenize the joint region by interdiffusion and to crystallographically orient the joint region by grain boundary migration, providing at the juncture a strengthened single crystal continuum. d) aging the single crystal continuum at a selected aging temperature for a selected time so that a uniform gamma prime content is produced throughout the continuum.