Chromate Conversion

Chromate conversion is a process that chemically alters the surface of a workpiece.  The process is performed in a solution of chromic acid.  The workpiece is immersed in the acidic solution, which decomposes some of the surface of the workpiece and creates a protective film of complex chromium compounds.

Process Characteristics

Is performed in a tank of chromic acid, which is usually a proprietary chrome salt solution of alodine or iridite
Changes surface chemical composition
Typically utilizes aluminum, cadmium, zinc, and zinc base as work materials
Is a relatively inexpensive way to prepare metal
Is usually associated with other cleaning and rinsing steps

BACK

Information provided is from Manufacturing Processes Reference Guide by Robert H. Todd, Dell K. Allen, and Leo Alting.--1st ed. Published by Industrial Press Inc., 1994.