 | Tomasz Lipiński BENDING FATIGUE STRENGTH COEFFICIENT THE LOW CARBON STEEL WITH IMPURITIES PRODUCTION ENGINEERING ARCHIVES 21(2018), pp.20-23 DOI: 10.30657/pea.2018.21.04 | |
Abstract The article discusses the results of a study investigating the effect of the number of fine non-metallic inclusions (up to 2 µm in size) on the fatigue strength of structural steel during rotary bending. The study was performed on 7 heats produced in an industrial plant. Fourteen heats were produced in a 100 ton oxygen converter. All heats were subjected to vacuum circulation degassing. Steel sections with a diameter of 18 mm were hardened and tempered at a temperature of 200, 300, 400, 500 and 600°C. The experimental variants were compared in view of the applied melting technol-ogy and heat treatment options. The heat treatments were selected to produce heats with different microstructure of steel, from hard microstructure of tempered martensite, through sorbitol to the ductile microstructure of spheroidite. The results were presented graphically, and the fatigue strength of steel with a varied share of non-metallic inclusions was determined during rotary bending. The results re-vealed that fatigue strength is determined by the relative volume of fine non-metallic inclusions and tempering temperature. | ||
Keywords steel structural steel non-metallic inclusions oxide impurities fatigue strength bending fatigue | ||