Revised Standard from Last Update.

NATIONAL FOREWORD

This Indian standard (Third Revision) which is identical with ISO 4957 : 2018 ‘Tool steels’ issued by the International Organization for Standardization (ISO), and subject to its finalization, is to be adopted by the Bureau of Indian Standards on the recommendation of the Alloy Steels and Forging Sectional Committee and approval of the Metallurgical Engineering Division Council.

This standard was first published in 1966 and subsequently revised in 1978 and 1990. While reviewing this standard, the Committee felt necessary to align it with latest international developments in this field. Accordingly, it has been decided to harmonize IS 3748 with the latest version of ISO 4957 : 2018 ‘Tool Steels’, which specifies requirements for tool steels comprising of non-alloy cold-work tool steels, alloy cold-work tool steels, alloy hotwork tool steels and high speed tool steels. This revision of IS 3748 replaces IS 3748 : 1990 ‘Tool and Die Steels’ and IS 7291 : 1981 ‘High Speed Tool Steels’. IS 7291 shall stand withdrawn subsequently.

The text of ISO standard has been approved as suitable for publication as in Indian Standard without deviations. Certain terminologies and conventions are, however, not identical with those used in Indian Standard. Attention is especially drawn to the following:

a) Wherever the words `International Standard’ appear referring to this standard, it should be read as `Indian Standard’

b) Comma (,) has been used as a decimal marker while in Indian Standards the current practice is to use a point (.) as the decimal marker.