Hydrogen Embrittlement in Steels: An Update

Some people incorrectly believe that they can tell if a part broke due to hydrogen embrittlement simply by looking at it. In addition to a macroscale brittle appearance, the timing of the crack is a key indicator. Furthermore, epistemological confidence must be created by examination at the microscale. Intergranular features ("rock candy"), a known source of hydrogen (often electroplating or pickling), a susceptible component (usually where the yield strength approaches the tensile strength), and freedom from other problems known to promote intergranular fracture (such as improper tempering temperature or slow cooling of very large components from hot processing, possibly even quench cracking) all must be documented before one may have a legitimate accusation of hydrogen embrittlement in steel parts.