Deutsches Institut fur Normung e. V.

Determination of the resistance of stainless steel to intergranular corrosion using the copper sulfate/sulfuric acid method (Moneypenny-Strauss Test)
 N 50914

Annotation

Scope and field of application

This standard describes an accelerated corrosion test for determining the resistance to intergranular corrosion of the stainless steels specified in DIN 17 440, DIN 17 445 and Stahi-Eisen-Werkstoffblatter (Iron and steel material specifications) 400 and 4101). If products are to come in contact with mildly oxidizing (or reducing) acid media, testing is carried out to determine susceptibility to intergranular corrosion. When the products under test are intended for use with neutral media, this method can indicate susceptibility to pitting and intergranular stress-corrosion cracking.

This method is not suitable for testing stainless steels which, due to their chemical composition or structure, remain active when immersed in the test solution, nor is it suitable for determining the corrosion resistance of products when exposed to extremely corrosive media.

The test method specified in this standard applies to rolled, forged and cast products, primarily to flat products and tubes with a thickness or wall thickness of 10 mm or less. The testing of flat products and tubes with a thickness or wall thickness greater than 10 mm, and of other product forms, is subject to agreement. When testing to provide proof of resistance to intergranular corrosion in accordance with tables 3 and 5 of DIN 17 440, product dimensions shall be as in DIN 17 440 or shall be agreed upon.

The corrosion testing of high alloy steels is dealt with in Stahi-Eisen-PrOfblatt (Iron and steel testing specification) 18771).

Normally, stainless steel is tested for resistance to intergranular corrosion for one of the following purposes2):