Method and apparatus for detecting stainless steel sensitization
US5262839A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1992 |
| Grant date | Nov 16, 1993 |
| Priority date | — |
| Expiry date | Mar 17, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N33/2045
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The susceptibility of austenitic stainless steel is tested by inputting a highly magnified image of the polished and etched steel surface through a microscope, a CCD camera and an input device into an image processor. The image processor is set up to identify grain boundary locations in the image, take width measurements across the grain boundaries, based on luminance distribution, and calculate average and maximum values for the measured widths. These calculated measured values are compared with experimentally-determined reference values -1 to 1.5 .mu.m for mean width and 2 to 3 .mu.m for maximum width - and a susceptibility status determined accordingly. The status can then be output using a display e.g. screen or printer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.