Get in touch with Zhenling Company
Standards trigger check
Does This Part Trigger a Stress Relief or an Embrittlement Bake?
Hydrogen embrittlement is the failure that arrives after delivery, which makes it a commercial problem as much as a technical one. ASTM B633 sets three separate thresholds — one before plating, one that forbids plating outright, and one after plating — and they are triggered by the strength of the part rather than by the finish. Enter what the drawing states.
B633 states its thresholds in MPa with HRC equivalents alongside: 1000 MPa is quoted with 31 HRC, and 1700 MPa with 247 ksi and 46 HRC.
Use the specified minimum for the material condition as heat treated, not a typical value from a datasheet.
Clause 6.4 attaches the stress-relief requirement to these operations at or above the strength threshold, not to every part.
Sources: ASTM B633-13 clauses 1.3, 6.4 and 6.5, and ASTM B850 Table 1 as referenced by B633. Zhenling Metal routes stress relief and embrittlement relief where the strength and hardness of the part trigger it, and records when the bake was run relative to plating.
![Shop-Floor Carbon Steel CNC Machining Guide [2026]](https://zhenlingmetal.com/wp-content/uploads/2026/08/carbon-steel-cnc-machining-handbook-r2-featured-150x150.png)
