Etching is used to reveal the microstructure of the metal through selective chemical attack. It also removes the thin, highly deformed layer introduced during grinding and polishing. In alloys with more than one phase, etching creates contrast between different regions through differences in topography or reflectivity.

What is the purpose of etching process?

Etching Is a Chemical or Electrolytic Process Used after Metallographic Grinding and Polishing Procedures. Etching Enhances the Contrast on Surfaces in Order to Visualize the Microstructure or Macrostructure.

What is etching and why is it done?

Etching is an intaglio printmaking process in which lines or areas are incised using acid into a metal plate in order to hold the ink. To prepare the plate for etching, it is first polished to remove all scratches and imperfections from the surface. ...