ISO 23430:2019

INTERNATIONAL ISO
STANDARD 23430
First edition
2019-12
Ships and marine technology —
Specification of high manganese
austenitic steel thin strips used for
LNG tanks on board ships
Reference number
©
ISO 2019
© ISO 2019
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ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Required specification. 2
5 Manufacture . 2
5.1 Steel-making practice . 2
5.2 Steel strips . 2
5.3 Dimension . 2
6 Chemical composition and mechanical properties . 2
6.1 Chemical composition . 2
6.2 Mechanical properties . 2
6.2.1 Requirements of tensile strength and yield strength . 2
6.2.2 Toughness requirements . 3
6.2.3 Bend test . 3
6.3 Supplementary requirements . 3
7 Test procedures . 4
7.1 Mechanical test . 4
7.2 Retest procedures . 4
8 Weldability . 4
9 Marking . 4
10 Documentation . 4
Bibliography . 5
Foreword
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This document was prepared by Technical Committee ISO/TC 8, Ships and marine technology,
Subcommittee SC 8, Ship design.
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iv © ISO 2019 – All rights reserved

Introduction
There have been several requirements regarding metallic materials for cryogenic applications since the
adoption of the IGC and IGF Codes. Recently, a new high manganese austenitic steel has been proposed
[2]
for thick plates and piping systems of LNG carriers and LNG-fuelled ships . However, only plates
with a thickness ranging from 6 mm to 30 mm are specified and the target tank capacity is limited to
30 000 m .
This document covers a newly developed high manganese austenitic steel for thin strip application. This
steel has mechanical properties comparable or even higher than those of materials for cryogenic service
[3] [4]
listed in both the IGC Code and IGF Code , with good weldability and good resistance to atmospheric
corrosion. Consequently, this high manganese austenitic steel is intended to satisfy the strength
requirements of the str
...