Corrosion Testing FAQs – 20 most frequent questions and answers

This Corrosion Testing FAQs section assembles the most frequently asked questions we receive from clients and companies regarding different Corrosion Testing procedures and tests.

Here are 20 most frequent Corrosion Testing FAQs

1. What are the most popular corrosion tests?

The most popular corrosion tests methods are ASTM B117 (Standard Practice for Operating Salt Spray (Fog) Apparatus), ASTM G85 (Standard Practice for Modified Salt Spray (Fog) Testing) and ASTM D5894 (Standard Practice for Cyclic Salt Fog/UV Exposure of Painted Metal)

2. What are the differences between ASTM B117, ASTM G85 and ASTM D5894?

ASTM B117 (neutral salt spray test) is arguably the best known and still the most used corrosion test in the world. It was developed back in the early 1940’s and, therefore, has been the reference standard for decades before other methods were developed. Numerous tests methods (like MIL-STD, SAE or even ASTM methods) still refer to ASTM B117 for corrosion testing even if more specific and more advanced test methods are now available. The main reason remains that so many companies around the world have so much data on the behavior of their products and materials based on ASTM B117 that they are reluctant to use newer methods and see decades of collected information become useless or, at least, less relevant.

ASTM G85 can be seen as an improved version of ASTM B117 to some extent. ASTM G85 use the basic principles of ASTM B117 but add the specificities of certain industry sectors in order to address their particularities. The use of a different salt combination (to emulate seawater for example) or a different pH are typical examples.

ASTM D5894 integrates more natural factors than traditional corrosion tests like ASTM B117 or ASTM G85. By integrating the effects of UV, temperature and humidity variations, ASTM D5894 improves the correlation with natural corrosion observed in the field. ASTM D5894 offers a “standard” recipe (ASTM G154 cycle 2 / ASTM G85 annex 5) and more and more industries adapt those test parameters to match their reality. For example, by increas