Within the last decades great efforts were made by the producers of wrought corrosion resistant
products to develop new alloys. The materials of construction for modern chemical process industry
(CPI) plants, petrochemical and other industries not only have to resist uniform corrosion. New alloys
must also have sufficient resistance against localized corrosion and stress corrosion cracking. These
industries have to cope with both the technical and commercial challenges of rigid environmental
regulations, the need to increase production efficiency, and at the same time possess the necessary
versatility to handle varied feed stock and upset conditions.(1) Due to the production routes in all these
companies, they concentrated on their standard products like plate, bar, wire and tube. All plants in the
chemical process industries however also need castings for pumps and valves in the piping systems,
connecting reactors and heat exchangers. In the past, only few foundries copied the analysis of the
new materials, aiming at the production of castings similar in corrosion resistance to the wrought alloys.
Prominent examples of highly corrosion resistant materials are Alloy 59 (UNS 06059) and Alloy 31
(UNS 08031) developed in wrought product forms, e. g. sheet, plate, strip and forging, in Germany.
Some years ago, a German foundry obtained a license to produce cast versions of these alloys with the
obligation to execute extensive testing of corrosion resistance and mechanical properties in direct
comparison with the wrought materials. This paper reports the results of these efforts in some very
corrosive media which are used in chemical plants. The tests were executed in the corrosion
laboratories of an internationally acknowledged chemical enterprise.