Corrosion testing Corrodkote

The CASS Test. In the copper-accelerated acetic acid salt spray (CASS) test (42), the positioning of the test surface is restricted to 15 2°, and the salt fog corrosivity is increased by increasing temperature and acidity, pH about 3.2, along with the addition of cupric chloride dihydrate. The CASS test is used extensively by the U.S. automobile industry for decorative nickel—chromium deposits, but is not common for other deposits or industries. Exposure cycle requirements are usually 22 hours, rarely more than 44 hours. Another corrosion test, now decreasing in use, for decorative nickel—chromium finishes is the Corrodkote test (43). This test utilizes a specific corrosive paste combined with a warm humidity cabinet test. Test cycles are usually 20 hours. 

A.STM. B380, Std. Method of Corrosion Testing of Decorative Tkctrodeposited Coatings hy the Corrodkote Procedure, American Society for Testing and Materials, Philadelphia, Pa., 1990. 

Methods for corrosion testing of decorative chromium electroplating by the Corrodkote procedure... 

Corrodkote corrosion test General rules for stationary outdoor exposure corrosion tests... 

ASTM Standard B 380 Standard Method of Corrosion Testing of Decorative Electrodeposited Coatings by tbe Corrodkote Procedure, Annual Book of ASTM Standards, Vol. 03.02, ASTM International, West Conshohocken, PA, 2001. 

Method of Corrosion Testing of Decorative Electrodeposited Coatings by the Corrodkote Procedure. 

Metallic and other non-organic coatings—Corrodkote corrosion test (CORR test)... 

B 380 Method o1 corrosion testing of decorative electrodeposited coatings by the Corrodkote... 

An accelerated corrosion test for some electrodeposits for anodic coatings on aluminum. Corrodkote test... 

It has been shown that chromium is virtually unattacked by the CASS test solution Nickel, on the other hand, is corroded at a substantial rate (about 0-072mm/y), the presence of the copper ions tending to maintain the nickel in an active state . Thus, in the CASS test (and in the Corrodkote test as well) accelerated galvanic corrosion of the nickel occurs at any discontinuities in the chromium layer. Good correlation between the results of the CASS test and the performance of plated parts in service has been reported . 

Although originally intended for evaluation of nickel-containing decorative electroplated coatings, the Corrod-kote test, ASTM B 380, has been used to qualify the performance of galvanized products for automotive applications. Apparently, the chloride ions introduced in this process provide a useful indication of automotive underbody performance for products such as tubing for containment of automotive fluids and other small components. The Corrodkote test applies a corrosive slurry to the... 

The CASS test and Corrodkote procedure are employed primarily for testing decorative chromium systems, with the CASS test ako being useful for testing anodized aluminum. These tests were developed to give a more rapid indication of corrosion resistance and a better correlation with service performance. They have come into prominence tis the most widely used modifications of the salt spray test because of their greater speed. Both tests employ cupric ion in the corrodant... 

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