| Abstract: | High‐strength NiCr23Mo16Al bars – Influence of cold reduction on mechanical properties and corrosion behaviour For application in highly corrosive environments with high demands on the mechanical properties of the alloys, cold reduced NiCrMo alloys are often the alloys of choice. This work examines the influence of cold reduction up to 42%, introduced by cold drawing on the mechanical properties and the corrosion behaviour of the alloy NiCr23Mo16Al. Tensile tests performed at 20°C, 204°C and 371°C show a linear increase in 0.2% yield strength up the maximum cold reduction of 42%. For all cold reductions and all test temperatures at least 16% elongation to fracture were achieved. Also the impact strength was as high as approx. 200 J even for the lowest test temperature of ? 40°C. Corrosion tests performed according to ASTM G 28 A/B and G 48 C/D showed no deterioration of the 42% cold reduced alloy in comparison to the solution annealed condition. Only for material, which was 15–30% cold reduced a minor, slightly unsatisfactory behaviour was observed, which was attributed to the strong inhomogenity of the microstructure, thus resulting in the formation of a local element between the severe deformed rim and the undeformed centre of the material. Current density‐potential curves measured in 1 M NaCl according to ASTM G 61/98 revealed no influence of cold deformation on the electrochemical behaviour of the alloy. |
