Standard Specification for Steel Bars Subject to Restricted End-Quench Hardenability Requirements
|Publication Date:||15 December 1992|
|ICS Code (Steel bars and rods):||77.140.60|
This 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.
In 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 A 304) 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.
This 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.