Potentiostatic Etching

  • E. E. Stansbury

Abstract

Potentiostatic etching is the selective corrosion of one or more morphological features of a microstructure resulting from the metal to be etched being held in a suitable etching electrolyte at a controlled potential. Independent control of potential is accomplished by potentiostats. These are instruments capable of holding the potential of a metal to prescribed values relative to a reference electrode placed in the environment solution. The selected potential determines if dissolution can occur. Measuring the current density, moreover, can establish the dependence of the etching or corrosion rate on the potential. In alloys, the etching rate dependence on the potential may differ significantly for different phases and other microstructural details such as grain boundaries and etch pits. Thus, once a correlation has been established between potential, environment, and selectivity of attack on micro-constituents, potentiostatic etching becomes an additional tool for revealing alloy morphology.

Keywords

Zinc Nickel Carbide Platinum Nitrides 

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Copyright information

© Van Nostrand Reinhold Company Inc. 1986

Authors and Affiliations

  • E. E. Stansbury
    • 1
  1. 1.Department of Materials Science and EngineeringUniversity of Tennessee-KnoxvilleUSA

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