Abstract: An extension is formed directly on an article by melting a compatible alloy preform within a ceramic mold, followed by cooling of the end under controlled conditions sufficient to cause an integral extension to solidify on the article. A ceramic mold is attached on the end of the article with a mold cavity that generally defines the shape of the extension to be formed. The mold may be formed in situ on a removable mandrel, or preformed and attached to the subject article. Extensions formed by the method of this invention have a microstructure that is continuous and compatible with that of the article. Such microstructures may include epitaxial growth of the extension from the microstructure of the article. The method establishes a temperature gradient within the article during solidification that may be further controlled by auxiliary heating and/or cooling of the article and/or extension during the practice of the method.