A downhole assembly comprises a first article; and a second article having a surface which accommodates a surface shape of the first article, wherein the first article is configured to provide a chemical, heat, or a combination thereof to facilitate the disintegration of the second article. A method comprises disposing a second article in a downhole environment; disposing a first article on the second article; the second article having a surface which accommodates a surface shape of the first article; performing a downhole operation; and disintegrating the first article to provide a chemical, heat, or a combination thereof that facilitates the disintegration of the second article.