Get to the bottom of those nasty arc burns and other heat affected areas using a nital etch test. Nital etch test is a test for checking machining damage or grinding burn of a hardened steel component. It’s also known as temper etch, nital inspection, nital NDT, MIL-STD-867C, AMS 2649C, etc. Machining or grinding can introduce a tremendous amount of heat into a steel component. If an area of the component is not cooled properly by a water jet, it will overheat. This can produce undesirable changes in the steel’s properties. An overheated area (over-tempered area) may not have any visible burn marks, but it can be identified using the nital etch test. The overheated area will appear darker than the surrounding area after the test.
For more information, see safety data sheet: ES Laboratory Acid Neutralizer – SDS
The ES Laboratory nital etch kit containing all three solutions is also available.