Osamu Furukimi* and Mitsuru Yanagisawa**
*Plate Laboratory, Kawasaki Steel Corporation
**System Development, Kawatetsu System Development Corporation
The image analysis has been developed using a digital image processing system (LUZEX 5000) with a gray memory unit which is enable to analyse an image by dividing the gray levels into 8 bits. The following examples of the application of image analysis to the metallurgical studies are introduced in this paper.
(1) Measurement of plate thickness after corrosion test:
The distribution of the plate thickness after corrosion test can be represented by the darkness of the soft X-ray film. Therefore, the distribution of the decrease in plate thickness due to corrosion can be represented as the two dimensional stereographic map by analysing the gray levels of soft X-ray film.
(2) Analysis of microstructure of the steel:
In the quenched and tempered martensite, prior austenite is divided into several bundles, and the bundle size is one of the important parameter of the toughness of the steel. The texture analysis were developed for several typical martensite structure using the image analysis method. The good relationship between the bundle size and the contrast parameter which is one of the texture parameters was found.
(3) Measurement of brittle fracture unit:
A brittle fracture unit is called facet. The facet size was measured by the contrast parameter.