1.1 This test method covers mechanical tests for the evaluation and control of the potential for hydrogen embrittlement that may arise from various sources of hydrogen as in plating processes, from fluids, cleaning treatments, maintenance chemicals, and gaseous environments that may contact the surface of steels.

1.2 The procedures and requirements are specified for five types of test specimens using a heat of AISI E4340 steel with demonstrated sensitivity. This test method is not intended to measure the relative susceptibility of other steels.

1.3 This test method assumes that AISI E4340 steel at 51HRC-54HRC, determined to be sensitive as specified in Table 1, is the worst case; that is, all other heat treated, high-hardness steels are less susceptible to hydrogen embrittlement.

1.4 For testing maintenance chemicals, the containment chamber must be isolated around the test specimen, as shown in Fig. 1 for Type 1a. If the test specimen and self-loading frame are to be immersed into the maintenance chemical, then the test fixture must be made from AISI E4340 steel except that it can be vacuum melted and heat treated to a lower hardness by tempering at 482 + 14°C (900 + 25°F) to a hardness of 40HRC-43HRC. This is done in order to minimize any polarization effects of galvanic coupling that would influence the test results.

1.5 Specimen geometries, equivalent loading conditions, and the pass/fail requirements for each type are also specified.

1.6 Classification -Hydrogen embrittlement tests can be performed with specimens as specified in the following:

1.6.1 Type 1-Notched:

1.6.1.1 Type 1a -Round bar, loaded in tension, under constant load.

1.6.1.2 Type 1b -Round bar, loaded in tension, with self-loading ring.

1.6.1.3 Type 1c -Round bar loaded in bending with self-loading frame.

1.6.1.4 Type 1d -C-rings loaded in bending with self-loading bolt.

1.6.2 Type 2 -Smooth (Unnotched).

1.6.2.1 Type 2a -Ring specimens loaded in bending with displacement bars.

1.7 This standard does not purport to address all of the safety problems, 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 of regulatory limitations prior to use.

1.8 This test method is limited to hydrogen embrittlement testing of steels that are exposed to the following:

1.8.1 An electrochemical plating process.

1.8.2 Maintenance chemicals, subsequent to cadmium plate.

1.9 The values stated in acceptable metric units shall be regarded as the standard.