Se~or

Designation: E18 – 08b

An American National Standard

Standard Test Methods for

Rockwell Hardness of Metallic Materials1,

2

This standard is issued under the fixed designation E18; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the Department of Defense.

1. Scope* 1.1 These test methods cover the determination of the Rockwell hardness and the Rockwell superficial hardness of metallic materials by the Rockwell indentation hardness principle. This standard provides therequirements for Rockwell hardness machines and the procedures for performing Rockwell hardness tests. 1.2 This standard includes additional requirements in annexes:
Verification of Rockwell Hardness Testing Machines Rockwell Hardness Standardizing Machines Standardization of Rockwell Indenters Standardization of Rockwell Hardness Test Blocks Guidelines for Determining the Minimum Thickness of aTest Piece Hardness Value Corrections When Testing on Convex Cylindrical Surfaces Annex A1 Annex A2 Annex A3 Annex A4 Annex A5 Annex A6

Rockwell superficial hardness tests. The significant differences between the two tests are that the test forces are smaller for the Rockwell superficial test than for the Rockwell test. The same type and size indenters may be used for either test, depending on thescale being employed. Accordingly, throughout this standard, the term Rockwell will imply both Rockwell and Rockwell superficial unless stated otherwise. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability ofregulatory limitations prior to use. 2. Referenced Documents 2.1 ASTM Standards:3 A370 Test Methods and Definitions for Mechanical Testing of Steel Products A623 Specification for Tin Mill Products, General Requirements A623M Specification for Tin Mill Products, General Requirements [Metric] B19 Specification for Cartridge Brass Sheet, Strip, Plate, Bar, and Disks B36/B36M Specification for BrassPlate, Sheet, Strip, And Rolled Bar B96/B96M Specification for Copper-Silicon Alloy Plate, Sheet, Strip, and Rolled Bar for General Purposes and Pressure Vessels B103/B103M Specification for Phosphor Bronze Plate, Sheet, Strip, and Rolled Bar B121/B121M Specification for Leaded Brass Plate, Sheet, Strip, and Rolled Bar B122/B122M Specification for Copper-Nickel-Tin Alloy, Copper-Nickel-Zinc Alloy (NickelSilver), and CopperNickel Alloy Plate, Sheet, Strip, and Rolled Bar B130 Specification for Commercial Bronze Strip for Bullet Jackets B134/B134M Specification for Brass Wire

1.3 This standard includes nonmandatory information in appendixes which relates to the Rockwell hardness test.
List of ASTM Standards Giving Hardness Values Corresponding to Tensile Strength Examples of Procedures forDetermining Rockwell Hardness Uncertainty Appendix X1

Appendix X2

1.4 Units—At the time the Rockwell hardness test was developed, the force levels were specified in units of kilograms-force (kgf) and the indenter ball diameters were specified in units of inches (in.). This standard specifies the units of force and length in the International System of Units (SI); that is, force in Newtons (N) andlength in millimeters (mm). However, because of the historical precedent and continued common usage, force values in kgf units and ball diameters in inch units are provided for information and much of the discussion in this standard refers to these units. 1.5 The test principles, testing procedures, and verification procedures are essentially identical for both the Rockwell and

1 These test...