NF EN ISO 643
Steels - Micrographic determination of the apparent grain size
This document specifies micrographic methods of determining apparent ferritic or austenitic grain size in steels. It describes the methods of revealing grain boundaries and of estimating the mean grain size of specimens with unimodal size distribution. Although grains are three-dimensional in shape, the metallographic sectioning plane can cut through a grain at any point from a grain corner, to the maximum diameter of the grain, thus producing a range of apparent grain sizes on the two-dimensional plane, even in a sample with a perfectly consistent grain size.
This document specifies micrographic methods of determining apparent ferritic or austenitic grain size in steels. It describes the methods of revealing grain boundaries and of estimating the mean grain size of specimens with unimodal size distribution. Although grains are three-dimensional in shape, the metallographic sectioning plane can cut through a grain at any point from a grain corner, to the maximum diameter of the grain, thus producing a range of apparent grain sizes on the two-dimensional plane, even in a sample with a perfectly consistent grain size.
This document specifies a micrographic method of determining apparent ferritic or austenitic grain size in steels. It describes the methods of revealing grain boundaries and of estimating the mean grain size of specimens with unimodal size distribution. Although grains are three-dimensional in shape, the metallographic sectioning plane can cut through a grain at any point from a grain corner, to the maximum diameter of the grain, thus producing a range of apparent grain sizes on the two-dimensional plane, even in a sample with a perfectly consistent grain size.
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1 Domaine d'application
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2 Références normatives
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3 Termes et définitions
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4 Symboles
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5 Principe
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6 Sélection et préparation de l'échantillon
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7 Caractérisation de la grosseur de grain
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8 Rapport d'essai
- A Méthodes de mise en évidence des joints de grains austénitiques et d'anciens joints de grains austénitiques dans les aciers
- B Détermination de la grosseur de grain par comparaison avec des images types
- C Méthode d'évaluation
- D Calcul de la grosseur de grain et de l'intervalle de confiance
- E Grains de différents indices de grosseur
- Bibliographie
At a glance, you will be able to identify the additions, deletions or modifications to a text, table, figure and formula.

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