Standard Specification for Steel Bars Subject to Restricted End-Quench Hardenability Requirements

Available format(s)

Hardcopy , PDF

Language(s)

English

Published date

01-11-2019

Publisher

American Society for Testing and Materials

1.1This specification covers hot-worked alloy and carbon-boron steels designed to attain restricted depth of hardening in the end-quench test. These steel compositions are identified by the suffix letter “RH” added to the conventional grade number.

1.2In general, steels with restricted hardenability (RH steels) will exhibit a hardness range not greater than 5 HRC at the initial position on the end-quench hardenability bar and not greater than 65 % of the hardness range for standard H-band steels (Specification A304) in the inflection region. Generally the restricted hardenability band follows the middle of the corresponding standard H-band. An example of the RH band compared with the H band is given for Grade 4140 in Fig. 1.

FIG. 1 Comparison of H-Band and RH-Band for 4140 Steel^A

1.2.1The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

1.3This specification is expressed in both inch-pound units and SI units. However, the material will be supplied to inch-pound units unless the purchase order specifies the “M” specification designation.

1.4This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

Committee	A 01
DocumentType	Standard
Pages	27
PublisherName	American Society for Testing and Materials
Status	Current
Supersedes	ASTM A 914/A914M : 2016

ASTM A 29/A29M : 2023	Standard Specification for General Requirements for Steel Bars, Carbon and Alloy, Hot-Wrought
ASTM E 112 : 2013 : R2021	Standard Test Methods for Determining Average Grain Size
ASTM E 112 : 2013	Standard Test Methods for Determining Average Grain Size
ASTM A 29/A29M : 2020	Standard Specification for General Requirements for Steel Bars, Carbon and Alloy, Hot-Wrought