ISO 16574:2015

INTERNATIONAL ISO
STANDARD 16574
First edition
2015-09-15
Determination of percentage of
resolvable pearlite in high carbon
steel wire rod
Détermination du pourcentage de perlite résoluble dans les fils
machine en acier à haut carbone
Reference number
©
ISO 2015
© ISO 2015, Published in Switzerland
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ii © ISO 2015 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 1
5 Principle . 2
6 Selection and preparation of samples . 2
6.1 Test location . 2
6.2 Grinding and polishing . 2
6.3 Etching . 2
7 Evaluation of the percentage of resolvable pearlite . 3
7.1 Parameters of optical microscope . 3
7.2 Determination of measuring field of view. 3
7.2.1 Determination of measuring locations . 3
7.3 Measuring methods . 4
7.3.1 Manual point count method . 4
7.3.2 Automatic image analysis method . 4
7.4 Reporting of results . 4
Bibliography . 5
Foreword
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The committee responsible for this document is ISO/TC 17, Steel, Subcommittee SC 7, Methods of testing
(other than mechanical tests and chemical analysis).
iv © ISO 2015 – All rights reserved

Introduction
This test method produces an estimate of the percentage of pearlite resolvable at 500x magnification
in wire rod as a function of the cooling method after hot rolling to rod. The drawability of high-carbon
pearlitic rod is influenced by the amount of resolvable pearlite present. As the percentage of resolvable
pearlite increases, drawability decreases. The methods are used to check if the content of resolvable
pearlite can fulfil the requirement of the wire rod with improved characteristics intended for drawing.
INTERNATIONAL STANDARD ISO 16574:2015(E)
Determination of percentage of resolvable pearlite in
high carbon steel wire rod
1 Scope
This International Standard defines resolvable pearlite and specifies two methods of determining the
percentage of resolvable pearlite.
The methods are applicable for wire rod made from control cooling steel with carbon content greater
than 0,65 % C.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
ind
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