MetaLube, Inc

Significance

Salt spray testing provides a controlled environment which is utilized to test relative corrosion resistance of rust preventative films, inorganic coatings, and organic coatings such as paints and primers.  It is commonly used to evaluate the performance of metal finishing products and practices.

Test Procedure

ASTM B117 outlines the standard practice for operating the salt spray chamber.  The test chamber maintains an internal temperature of approximately 95F, and produces a saturated, 100% RH environment using a 5% salt solution to produce the fog.  Test specimens are placed inside the test chamber for a period of time determined by performance requirements of the particular customer or application.   

ASTM D1654 details the method for evaluation of corrosion performance of painted or coated specimens subject to the salt spray environment dictated in ASTM B117.  Painted specimens are typically scribed through the paint film to expose the basis metal.  After a period of exposure to the salt fog, paint delamination (referred to as creep) is rated as outlined in the following table.  Results for scribed specimens are reported as a rating number at an exposure time.  Customers will require various ratings and time periods based on the final use of their products.