+ Visit NASA.gov + Contact NASA   + Home Collection > NACA  Author > Harrison, William N  Author > Mason, Mary A  Author > Moore, Dwight G  NASA Center > NASA (non Center Specific)  Publication Year > 1951-1960 > 1953  Availability Options > Online > PDF  Item/Media Type > NACA Report > Reports (TR)  Note: Start a new navigation search by selecting a link above     Previous Record | Next Record + Back to Results   + Printer Friendly Title: Relative importance of various sources of defect-producing hydrogen introduced into steel during application of vitreous coatings Author(s): Moore, Dwight G; Mason, Mary A; Harrison, William N Abstract: When porcelain enamels or vitreous-type ceramic coatings are applied to ferrous metals, there is believed to be an evolution of hydrogen gas both during and after the firing operation. At elevated temperatures rapid evolution may result in blistering while if hydrogen becomes trapped in the steel during the rapid cooling following the firing operation gas pressures may be generated at the coating-metal interface and flakes of the coating literally blown off the metal. To determine experimentally the relative importance of the principal sources of the hydrogen causing the defects, a procedure was devised in which heavy hydrogen (deuterium) was substituted in turn for regular hydrogen in each of five possible hydrogen-producing operations in the coating process. The findings of the study were as follows: (1) the principal source of the defect-producing hydrogen was the dissolved water present in the enamel frit that was incorporated into the coating. (2) the acid pickling, the milling water, the chemically combined water in the clay, and the quenching water were all minor sources of defect-producing hydrogen under the test conditions used. Confirming experiments showed that fishscaling could be eliminated by using a water-free coating. NASA Center: NASA (non Center Specific) Publication Year: 1953 Document Source: CASI Online Source: View PDF File Document ID: 19930092156 Accession ID: 93R21446 Publication Information: Number of Pages = 12 Report Number: NACA-TR-1120 Price Code: A03 Related Information: Also bound with NACA Annual Report 39-VOL-1, p. 269-280. Supersedes NACA Technical Note 2617.; NACA Technical Report 1120. Keywords: STEELS; COATINGS; VITREOUS MATERIALS; DEFECTS; HYDROGEN; SOURCES; ENAMELS; WATER; FRIT; PORCELAIN; CERAMIC COATINGS; Accessibility: Unclassified; No Copyright; Unlimited; Publicly available; Updated/Added to NTRS: 2009-01-14 + Back to Top + Sponsored by the NASA Scientific and Technical    Information Program + 2004 Vision for Space Exploration + Freedom of Information Act + NASA Web Privacy Policy and Important Notices + NASA Disclaimers, Copyright Notice,    and Terms and Conditions of Use NASA Official: Calvin Mackey Page Curator: NASA Center for AeroSpace Information (help@sti.nasa.gov) Last Updated: July 5, 2007