MIL-R-81294 Figure 3 notched C-ring test specimen

MIL-R-81294 §4.6.4.3 Hydrogen Embrittlement Test Specimens

Metal test specimens per military specification MIL-R-81294 §4.6.4.3 (Hydrogen Embrittlement Tests). This section describes two different tests, which use a notched C-ring specimen or an unnotched ring specimen (ASTM F519, Type 2a specimen). The notched C-ring specimens are made from 4130 steel, and are machined, heat treated, cleaned, and cadmium plated per MIL-R-81294 §4.6.4.3.1.1. The test procedure requires four ring specimens for each test. Customized specimens for modified versions of this test method are available on request.