| Abstract: | Qualification of new corrosion-resistant materials for chemical plants and equipment The publication quotes the “superaustenite” X 2 NiCrMoCu 25 20 5 (Cronifer 1925 LC/Alloy 904 L, 1.4539) as an example how to distinctly improve the resistance to local corrosion in acid and neutral chloride-containing media by reducing the sulfur content and increasing the content of nitrogen, while simultaneously influencing the mechanical characteristics in a positive way. As a result, a new material for chemical plants and equipment, Cronifer 1925 LCN/Alloy 904 LN is presented. In a second part the article explains how by its reduced carbon content and change in alloying constituents the Ni alloy GiCrFeMoCu (Nicrofer 4823 hMo/Alloy G-3 (2.4619)) might be interpreted as a progressive modification of the more conventional NiCr 21 Mo (Nicrofer 4221/Alloy 825 (2.4858)) type ein order to meet new requirements. The report specially deals with the susceptibility to sensitization in processing as well as with the resistance to local corrosion in acid chloride-containing media, thanks to which Nicrofer 4823 hMo can be ranked between austenitic steels and very highly alloyed Nibase materials as to its application fields. |
