Treating composition, forming a mixed-carbide layer of Va-Group elements and of chromium on a ferrous-alloy surface and resulting product

摘要

A method and treating material are presented for forming a mixed-carbide layer of at least one Va-Group element and of chromium on the surface of a carbon-containing ferrous-alloy material. A molten treating bath is prepared by introducing one or more Va-Group elements in oxide form and chromium in metal or alloy form or by introducing one or more Va-Group elements in metal or alloy form and at least one chromium oxide into a molten bath composed of boric acid, of at least one borate or of a mixture thereof. An article of carbon-containing ferrous alloy is immersed and maintained in the molten treating bath until a mixed-carbide layer is formed on its surface. The mixed-carbide layer formed on the surface of the article is very smooth, wear resistant and high-temperature-oxidation resistant.