Effect of Grain Boundary Structure on Sensitization and Corrosion of Stainless Steel.
Abstract
This paper reports on a study of intergranular corrosion, particularly the influence of the crystallography of a grain boundary (g.b.) on the sensitization and grain boundary corrosion of stainless steels. Since sensitization of stainless steels depends on g.b. energy, this study included a determination of the misorientation angle of grain boundaries in a sample. A scanning electron microscope was modified for application of the electron backscattering (EBS) technique in conjunction with normal SEM imaging of the sample surface. In austenitic stainless steel (Fe-18Cr-10Ni) samples annealed at 1200 C for 1 hour., water quenched and aged for various times at 650 C, the degree of sensitization increased with increasing aging time. This was indicated by an increasing width of the g.b. groove . A plot of grove width vs. g.b. misorientation angle obtained by the EBS technique showed a range of groove crystallography and the coincident site lattice concept provided a rationalization of this observation. Similiar results were found for ferritic stainless steel (Fe-19 Cr) samples. The Cr concentration profiles as a function of time were calculated, using a finite difference method, both along the g.b. and normal to the g.b.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1985
- Accession Number
- ADA157133
Entities
People
- B. W. Bennett
- H. W. Pickering
Organizations
- Pennsylvania State University