Laboratory Testing of Metals for Resistance to Sulfide Stress Cracking and Stress Corrosion Cracking in H₂S Environments

The primary purpose of this standard is to facilitate conformity in testing so that data from different sources can be compared on a common basis. Consequently, this standard aids the evaluation and selection of all types of metals and alloys, regardless of their form or application, for service in H₂S-containing environments. This standard contains methods for testing metals using uniaxial tensile, three-point bent-beam, C-ring, and double-cantilever-beam (DCB) test specimens. A separate standard, NACE TM0316,³ contains a method for testing metals using four-point bend test specimens.

This test method may be used for many purposes, and the applications of the test results are beyond the scope of this standard. Those who use the test method should be aware that, in some cases, the test results can be influenced by variations in properties among different locations in a single length of pipe, individual plate, or weld, as well as by variations within a heat of steel. When the test method is used as a basis for purchasing, the number and location of the test specimens must be carefully considered. This standard is intended for end users, manufacturers, fabricators, and testing laboratories.

The new revision of this standard reflects industry needs and the better harmonization of testing practices. The main changes are as follows. In Paragraph 4.5, a cleaning procedure was added for each test method. In Section 6, the general information was clarified, and the specific test solution definition was revised with accommodation for expanded industry needs, including deaeration and saturation procedures. In Section 7, clarification and standardization of testing under non-ambient conditions were added. In Section 11, a detailed pre-cracking procedure was added and fracture surface evaluation exemplars were added for easier interpretation. Appendixes A, B, and C (all nonmandatory) are unchanged. However, reporting requirements for all test Methods (A, B, C, and D) were revised and qualification reporting tables were transferred to a new Appendix D (nonmandatory) titled “Recommended Reporting Template for ANSI/NACE MR0175-2021/ISO 15156:2020 Material Qualification” to enhance readability of the document. Appendix E (nonmandatory) was added, titled “Recommendations for Precracking of DCB Specimens for Method D (DCB Test).” The former Appendix E is now Appendix F (nonmandatory). Finally, Appendix G (formerly Appendix D) was revised from a nonmandatory appendix to mandatory and a second compliance method was added.