SCANNING

The Journal of Scanning Microscopies

 
 

Search the SCANNING website



Zeiss -- Total Solutions for Laser Scanning Microscopy
Please visit our advertiser
Note to authors:
All new manuscripts must be submitted online at:
http://scanning.msubmit.net

SCANNING VOL. 27, 132–135 (2005)
Received: June 23, 2004
Accepted with revision: December 3, 2004
© FAMS, Inc.

Porosity Determination of Ceramic Materials by Digital Image Analysis–A Critical Evaluation

M. von Bradke, F. Gitzhofer,* R. Henne

German Aerospace Center (DLR), Institute of Technical Thermodynamics, Stuttgart, Germany; *Université de Sherbrooke, Department of Chemical Engineering, Faculty of Engineering, CREPE, Sherbrooke, Quebec, Canada

Full-text (for Scanning subscribers)

Summary: Measuring the porosity of materials by digital image analysis of micrographs is a well-established and convenient method for the testing of metallic samples. However, when applied to ceramic materials, this method has been shown to be much less reliable and poorly reproducible. The purpose of this present work is to clarify the reason for this deficiency, involving many porosity measurements, performed on plasma-sprayed zirconia, under systematically varied microscopic imaging conditions, and the porosities being calculated using various evaluation methods. Comparison between of the results has shown that the present state of the image analysis method is not satisfactory for absolute porosity measurements on ceramic materials. It can be useful as a convenient tool for comparative measurements, however, if the imaging conditions maintained in the microscope and the evaluation method are held to be exactly identical.

Key words: scanning electron microscopy, image analysis, porosity determination, metallographic preparation, grey level histogram

PACs: 06.30.Bp, 06.60.Mr, 07.78.+s

Address for reprints:
Francois Gitzhofer
Universite de Sherbrooke
2500 Boul Universite
Bureau C1-5048
Sherbrooke, PQ J1 K2R1, Quebec
Canada