Metallographic Etchants

Metallographic etchants are chemicals that can reveal microstructural details that would otherwise not be evident on an as-polished sample. Metallographic etching can be done by immersion or swabbing the surface with an etchant. The etchant will selectively corrode microstructural features, such as grain boundary, hardening case, or different metal phases. These features can then be studied with a microscope. Most of the samples need to be mirror polished and etched as soon as possible to prevent its surface from oxidation or passivation. The etching time is highly dependent on the sample and in most cases requires experience. However, few seconds to a minute are typical. Some hard-to-etch or soft metals require an etch-polish-etch cycle to get the best results.

The selection of the optimum etchant is very important in sample preparation. We carry all the popular metallographic etchants found in the ASTM Standard for etching iron, carbon steel, stainless steel, superalloy, titanium, aluminum, copper, bronze, brass, and others. If you have any questions about our products, please give us a call. We can test your sample and recommend a suitable product based on the test result.