NF EN ISO 21821

NF EN ISO 21821

November 2022
Standard Current

Fine ceramics (advanced ceramics, advanced technical ceramics) - Determination of densification properties of ceramic powders on natural sintering

This document specifies the test method to determine the extent to which ceramic powder compacts made of granulated or ungranulated ceramic powders are densified, when they are sintered at a high temperature without the application of any external pressure or external densification force. The test method is applicable to pure oxides, mixtures of oxides and solid solutions, and is also applicable to non-oxides (e.g. carbides, nitrides) that can be sintered under vacuum or constant gas pressure (1 bar or less) to prevent oxidation or decomposition. The test method is not applicable to ceramics that can only be sintered using pressure-assisted sintering techniques such as hot pressing (HP), hot isostatic pressing (HIP), gas pressure sintering (GPS) or spark plasma sintering (SPS). Inorganic sintering additives can be used where their presence is reported.

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Main informations

Collections

National standards and national normative documents

Publication date

November 2022

Number of pages

22 p.

Reference

NF EN ISO 21821

ICS Codes

81.060.30   Advanced ceramics

Classification index

B42-011

Print number

1

International kinship

ISO 21821:2019

European kinship

EN ISO 21821:2022
Sumary
Fine ceramics (advanced ceramics, advanced technical ceramics) - Determination of densification properties of ceramic powders on natural sintering

This document specifies the test method to determine the extent to which ceramic powder compacts made of granulated or ungranulated ceramic powders are densified, when they are sintered at a high temperature without the application of any external pressure or external densification force. The test method is applicable to pure oxides, mixtures of oxides and solid solutions, and is also applicable to non-oxides (e.g. carbides, nitrides) that can be sintered under vacuum or constant gas pressure (1 bar or less) to prevent oxidation or decomposition. The test method is not applicable to ceramics that can only be sintered using pressure-assisted sintering techniques such as hot pressing (HP), hot isostatic pressing (HIP), gas pressure sintering (GPS) or spark plasma sintering (SPS). Inorganic sintering additives can be used where their presence is reported.

Replaced standards (1)
NF EN 725-11
October 2006
Standard Cancelled
Advanced technical ceramics - Methods of test for ceramic powders - Part 11 : determination of densification on natural sintering

Le présent document décrit une méthode de détermination de la densification des poudres céramiques lors du frittage naturel, sans l'application d'une quelconque pression extérieure. Cette méthode s'applique aux oxydes purs, aux mélanges d'oxydes et aux solutions solides. Il est possible d'utiliser des additifs de frittage inorganiques à condition de signaler leur présence.

Table of contents
  • 1 Domaine d'application
  • 2 Références normatives
  • 3 Termes et définitions
  • 4 Principe
  • 5 Symboles et désignation
  • 6 Appareillage
  • 7 Prélèvement
  • 8 Mode opératoire
  • 9 Expression des résultats
  • 10 Rapport d'essai
  • Bibliographie
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