ISO 12986-2:2014

INTERNATIONAL ISO
STANDARD 12986-2
Third edition
2014-06-15
Carbonaceous materials used in the
production of aluminium — Prebaked
anodes and cathode blocks —
Part 2:
Determination of flexural strength by
the four-point method
Produits carbonés utilisés pour la production de l’aluminium —
Anodes précuites et blocs cathodiques —
Partie 2: Détermination de la résistance à la flexion par la méthode
quatre points
Reference number
©
ISO 2014
© ISO 2014
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Published in Switzerland
ii © ISO 2014 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus . 2
6 Test specimen . 3
6.1 Sampling and sample preparation . 3
6.2 Size and geometry . 4
7 Procedure. 4
8 Calculation and expression of results . 4
8.1 Bending moment, M .
b 4
8.2 Flexural strength, σ .
b 5
9 Precision . 6
10 Test report . 6
Bibliography . 7
Foreword
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The committee responsible for this document is ISO/TC 226, Materials for production of primary
aluminium.
This third edition cancels and replaces the second edition (ISO 12986-2:2009), which has been technically
revised.
ISO 12986 consists of the following parts, under the general title Carbonaceous materials used in the
production of aluminium — Prebaked anodes and cathode blocks:
— Part 1: Determination of bending strength by the three-point method
— Part 2: Determination of flexural strength by the four-point method
iv © ISO 2014 – All rights reserved

INTERNATIONAL STANDARD ISO 12986-2:2014(E)
Carbonaceous materials used in the production of
aluminium — Prebaked anodes and cathode blocks —
Part 2:
Determination of flexural strength by the four-point
method
1 Scope
This part of ISO 12986 specifies a four-point method to determine the flexural strength of carbon and
solid graphite materials at room temperature.
NOTE This part of ISO 12986 is based on DIN 51944.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 4288, Geometrical Product Specifications (GPS) — Surface texture: Profile method — Rules and
procedures for the assessment of surface texture
ISO 7500-1, Metallic materials — Verification of static uniaxial testing machines — Part 1: Tension/compression
testing machines — Verification and calibration of the force-measuring system
ISO 8007-1, Carbonaceous materials used in the production of aluminium — Sampling plans and sampling
from individual units — Part 1: Cathode blocks
ISO 8007-2, Carbonaceous materials used in the production of aluminium — Sampling plans and sampling
from individual units — Part 2: Prebaked anodes
ISO 8007-3, Carbonaceous materials used in the production of aluminium — Sampling plans and sampling
from individual units — Part 3: Sidewall blocks
...