ISO 642:2024 鋼 - 端部焼入れによる焼入れ性試験（ジョミニー試験） | ページ 2

Foreword

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This document was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 7, Methods of testing (other than mechanical tests and chemical analysis), in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 459, ECISS - European Committee for Iron and Steel Standardization, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This third edition cancels and replaces the second edition (ISO 642:1999), which has been technically revised.

The main changes are as follows:

• updated the normative references;
• added a new symbol, Jd, in Table 1;
• minimum recommended reduction ratio of 5:1, see 6.1;
• revised the test piece dimensions, see 6.1, 6.2 and Figures 1 and 2;
• revised the heat treatment requirements, see 6.3;
• revised configuration of fixing and centring device, see 7.3 and Figure 3;
• revised text concerning water temperature, see 7.4;
• revised requirement for nitric acid solution concentration, see 9.2;
• revised codification of test result, see 10.4 and Figure 6;
• revised A.2 and Figures A.2 and A.3;
• revised Annex C and Bibliography;
• editorial clarifications;
• reduced the number of bibliographical references.

1 Scope

This document specifies a method for determining the hardenability of steel by end quenching (Jominy test) by using a test piece 25 mm in diameter and at least 100 mm long.

By agreement and for a defined field of application, the test described in this document can be replaced by the calculation of the Jominy curve according to an accepted mathematical model.

2 Normative references

There are no normative references in this document.

3 Terms and definitions

No terms and definitions are listed in this document.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

Bibliography