Papers by Keyword: High Strength Low Alloy HSLA Steel

Abstract: The contribution of nano-scale particles observed using Atom Probe Tomography in an increase of yield strength of conventional and advanced HSLA steels was studied. The advanced HSLA steel showed higher yield strength than conventional HSLA steel. There were two types of carbides, which primarily contribute to an increase in yield strength of conventional HSLA steel: (i) coarse TiC with average size of 25±5nm and (ii) fine TiC with average radius of 3±1.2nm. The presence of two types of carbides was found in the microstructure of advanced HSLA steel: (i) nano-scale Ti0.98Mo0.02C0.6 carbides with average radius of 2.2±0.5nm, and (ii) C19Cr7Mo24 particles with an average radius of 1.5±0.3nm. The contribution of precipitation hardening in the yield strength of advanced HSLA steel due to the nano-scale particles was 174MPa, while this value in the conventional HSLA steel was 128MPa.

Abstract: The fatigue behavior assessment of high strength low alloy steel has main importance for reliable and safe service of welded structure. The mechanisms of fatigue crack initiation and propagation always represent a potential danger of crack propagation during the exploitation of a structure, which can lead to catastrophic failure. If the fatigue’s crack appear at the welded structure it is important to reliable find loading regime which can reduce risk of failure for still operating structure.