Computer aided determination of porosity in sintered steels

• Autorzy: Dobrzański, L. , Musztyfaga, M. , Actis Grande, M. , Rosso, M.
• Języki publikacji: PL

Abstrakty

EN

Purpose: Purpose of this paper was to apply a computer method of open porosity analysis for determination of porosity in sintered Astaloy CrL and CrM powders. Design/methodology/approach: The powders used in the present papier are pre-alloyed iron-base powders containing low amounts of chromium and molybdenum. The amount of graphite which is mixed with the iron-base powder is 0.6% and lubricant is 0.75%. Green compacts were sintered in a vacuum furnace at 1120°C for 30 minutes in vacuum and rapidly cooled in nitrogen at four different rates: high cooling (7°C/s and 6.5 °C/s) and medium cooling (1.6°C/s) low cooling (0.3 °C/s). Next the samples were tempered in vacuum in the same furnace at 200°C for 60 minutes and cooled in nitrogen, with the exception of low cooling. Obtained samples were examined by light optical microscopy (LOM) for microstructure observation and scanning electron microscopy (SEM). Findings: The investigations of porosity in the pre-alloyed steels were performed using ”Image-Pro Plus 4.5” computer program. Leica light microscope (MEFA4) was applied to prepare series of micrographs. The microstructures were observed at 100x magnification and recorded as*jpg files. After calibration of the digital images, the perimeter, area, diameter, roundness, Feret max were calculated. Practical implications: The program has some limitations (built in mathematical functions), which made difficult to obtain some results automatically. Originality/value: The obtained results prove that this program is very useful in the statistical analysis of microstructures, because it saves the time during calculations and is well suited for checking sintered materials.

Słowa kluczowe

PL

metalurgia proszków

EN

powder metallurgy; Sintering pre-alloyed astaloy CrL and CrM steels; Computer method of porosity analysis

• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2009
• Tom: Vol. 38, nr 2
• Strony: 103-111
• Opis fizyczny: Bibliogr. 15 poz.

Twórcy

autor

Dobrzański, L.

autor

Musztyfaga, M.

autor

Actis Grande, M.

autor

Rosso, M.

• Division of Materials Processing Technology and Computer Techniques in Materials Science, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland,

Bibliografia

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