Image Analysis (IA) - Paxit®
The Paxit® quantitative image analysis (IA) system is a very useful tool for statistical analysis of metallographic samples provided there is sufficient contrast between the features of interest and the surrounding material. The computer stores images, data, routines and results for future use. The system is a more accurate and repeatable alternative to the manual, and time consuming, sample characterization techniques. Results may be printed directly or output to MS Word or Excel.
Most specimens must be metallographically prepared prior to image analysis, but improper preparation can lead to erroneous results. For more detailed information refer to the section on Metallography / Optical Microscopy.
The IA system consists of the following components:
- Paxit® Image Analysis System (IA)
- Olympus® PMG3 Research Metallograph (inverted microscope)
- Olympus® SZH Stereo Microscope
- A macro stand for low magnification image analysis
- A flat bed scanner for macro-etched weld samples
Microstructural features amenable to IA technoques:
- Determining ASTM grain size
- Volume fractions of different phases in polymers or metals
- Decarburization depths in carbon steels
- Depth of sub-surface oxides
- Measurement of coating thickness
- Measurement of porosity
- Counting and sizing of organic and inorganic powders
- Size, shape and distribution of non-metallic inclusions in steel
- Nodular graphite in cast iron
- Ceramic materials
- Composites
- Grain contrast differences
- Carbide morphologies
IA typically consists of the following five steps:
- Image acquisition
- Image enhancement
- Feature detection
- Feature selection and editing
- Quantitative measurement
