| Abstract: | Corrosion resistance of chromium nickel cast steel (types 18/9 and 18/13) within increased silicon content in concentrated nitric acid solutions The corrosion resistance of CrNi cast steel, types 18/9 and 18/13, with different carbon (0.035-0.12%) and silicon (appr. 4%) contents was investigated in nitric acid (27-96%) eventually containing Cr6+ ions between 25 and 100°C. In this connection mechanical properties and structure of the above cast steels were determined, too. It has been found that in the case of 80% nitric acid solutions and of nitric acid solutions of higher or lower concentrations but containing Cr6+ ions the cast steel must have a silicon content of appr. 4% together with a carbon content as low as possible. The results of the laboratory tests have been confirmed unter industrial conditions. |
