ISO 11706:2012

INTERNATIONAL ISO
STANDARD 11706
First edition
2012-09-01
Carbonaceous materials for the
production of aluminium — Prebaked
anodes — Determination of the
fracture energy
Produits carbonés pour la production de l’aluminium - Anodes
précuites - Détermination de l’énergie de rupture
Reference number
ISO 11706:2012(E)
©
ISO 2012

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ISO 11706:2012(E)
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ISO 11706:2012(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
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electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International
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casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 11706 was prepared by Technical Committee ISO/TC 226, Materials for the production of primary
aluminium.
© ISO 2012 – All rights reserved iii

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INTERNATIONAL STANDARD ISO 11706:2012(E)
Carbonaceous materials for the production of
aluminium — Prebaked anodes — Determination of the
fracture energy
1 Scope
This International Standard describes a method for the determination of the fracture energy at room
temperature. This property is relevant for the thermal shock resistance of prebaked anodes used in the
electrolytic cell.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 8007-2, Carbonaceous materials used in the production of aluminium — Sampling plans and sampling
from individual units — Part 2: Prebaked anodes
ISO 12986-1, Carbonaceous materials used in the production of aluminium — Prebaked anodes and cathode
blocks — Part 1: Determination of bending/shear strength by a three-point method
ISO 12985-1, Carbonaceous materials used in the production of aluminium — Baked anodes and cathode
blocks — Part 1: Determination of apparent density using a dimensions method
3 Principle
The amount of energy needed to fracture a notched cylindrical test piece is determined by integrating
the force-displacement signals of the testing machine.
Notching of the test piece allows to minimize the elastic energy stored in the specimen and therefore
guarantees controlled and smooth crack propagation.
The same arrangement and testing equipment as required for the determination of the bending/shear
strength by a 3-point method can be used, see ISO 12986-1.
A length measurement device for the vertical displacement, a data acquisition system and software able
to integrate the force-displacement curve are additionally needed.
4 Apparatus
4.1 Testing equipment
The testing machine has a hydraulic system that can be adjusted to control the load increa
...