Prediction of Hydrogen Entry and Permeation in Metals and Alloys
Abstract
This report summarizes results of the past year on our continuing experiments directed to the problem of hydrogen entry and degradation of materials both of planar surfaces and for the more complicated recessed surface. For the planar surface the hydrogen permeation and scanning tunneling microscopy (STM) techniques are being used, and for the recessed surface the study uses the hydrogen permeation technique and a microscopy/electrochemical probe technique. In-situ scanning tunneling microscopy (STM) of hydrogen adsorption from the gas phase on Si 111(7x7) demonstrates the feasibility of STM for atomic scale study of adsorbed hydrogen. In aqueous solutions both acidification and chloride ion accumulation within recesses in iron surfaces cause enhanced proton reduction and hydrogen absorption. Flat, smooth surfaces can form or develop recesses as a result of corrosion or other reasons, e.g., grain boundary grooves that form during corrosion of Cr-depleted alloy in sensitized stainless steel. These recesses are found to be just as prone to proton discharge and hydrogen absorption as pre-existing recesses.... Scanning tunneling microscopy, Hydrogen permeation cell, Hydrogen absorption, Chloride ion and acidification effects, Hydrogen evolution in recesses, Corrosion-produced recesses, Grain boundary grooves.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1993
- Accession Number
- ADA260580
Entities
People
- Howard W. Pickering
Organizations
- Pennsylvania State University