ASTM E18-02 pdf free.Standard Test Methods for Rockwell Hardness and Rockwell Superficial Hardness of Metallic Materials.
These test methods cover the determination of the Rockwell hardness and the Rockwell superficial hardness of metallic materials, including test methods for the verification of machines for Rockwell hardness testing (Part B) and the calibration of standardized hardness test blocks (Part C).
4. Significance and Use
4.1 The Rockwell hardness test is an empirical indentation hardness test. Rockwell hardness tests provide useful informa- tion about metallic materials. This information may correlate to tensile strength, wear resistance, ductility, and other physical characteristics of metallic materials, and may be useful in quality control and selection of materials.
4.2 Rockwell hardness testing at a specific location on a part may not represent the physical characteristics of the whole part or end product.
4.3 Rockwell hardness tests are considered satisfactory for acceptance testing of commercial shipments, and have been used extensively in industry for this purpose.
4.4 Performance verifications of Rockwell hardness indenters and hardness machines shall be made using test blocks calibrated traceable to the Rockwell standards maintained b NIST when primary reference test blocks are available from NIST for the specific Rockwell scale.
5. Principles of Test and Apparatus
5.1 General Principles-The general principles of the Rockwell hardness test are illustrated in Fig. I(diamond indenter)and Fig. 2 (ball indenters) and the accompanyin Table I and Table 2. In the case of the Rockwell superficial test the general principles are illustrated in Fig. 3 (diamond indenter) and Fig. 4 (ball indenter)and the accompanying Table 3 and Table 4.
5.1.1 See Equipment Manufacturers Instruction Manua for a description of the machines characteristics, limitations and respective operating procedures. Typical applications of the various hardness scales are shown in Tables 5 and 6 Rockwell hardness values are usually determined and reported in accordance with one of these standard scales. An indenter is forced into the surface of a test piece in two steps under specified conditions(see Section 7) and the difference in depth of indentation is measured as e.