Comparison of responses of different types of steel alloys under the same loading and environmental conditions

Abstract

Modern construction must meet the function for which it has been made and must be safe and economical to operate. In order to achieve the foregoing, the design of the structure should strive for an optimal solution. Such a design is usually based on the optimal choice of material and the optimal dimensions of structural elements. In order to select the optimal material for the manufacture of structural elements, it is necessary to have data on the behavior of the material in the intended operating conditions. In this sense, this paper deals with experimental research and analysis of the behavior of several types of materials subjected to approximately the same operating conditions. Under considerations were low-alloy structural steel (1.7225), special structural steel (1.7147), alloy carbon steel (1.5920), and alloy stainless steel (1.4034). The mechanical behavior of the tested materials, in terms of monitoring changes and mutual comparisons of mechanical properties, is shown on the basis of engineering stress–strain diagrams, while their creep resistances are monitored and compared with each other based on creep curves. As for the fracture toughness, it can be estimated based on the results of the fracture impact energy test, applying the known calculation method. In accordance with the tests performed at room temperature, the following results related to the maximum ultimate tensile strength ( ${\sigma }_m$ /MPa), Charpy V-notch impact energy (CVN/J), and fatigue limit ( ${\sigma }_f/\mathrm{MPa})$ at stress ratio $R$ , are shown as follows: [Mat. Nr. ${\left[\left({\sigma }_m/\mathrm{MPa};\mathrm{ }\mathit{CVN}/\mathrm{J};\mathrm{ }{\sigma }_{f,R}/\mathrm{MPa}\right)\right]}_{20},\mathrm{ }{\mathrm{and}\mathrm{ }\mathrm{their}\mathrm{ }\mathrm{magnitudes}\mathrm{ }\mathrm{are}:\left[1.7225\mathrm{ }\left(733;\mathrm{ }166;\mathrm{ }{532}_{0.25}\right)\right]}_{20}$ ; ${\left[1.7147\mathrm{ }\left(560;\mathrm{ }178;\mathrm{ }-\right)\right]}_{20}$ ; ${\mathrm{ }\left[1.5920\mathrm{ }\left(612;\mathrm{ }220;\mathrm{ }{285}_{-1}\right)\right]}_{20}$ ; ${\left[1.4034\mathrm{ }\left(782;\mathrm{ }8;\mathrm{ }{325}_{-1}\right)\right]}_{20}$ .