Análisis de microgrietas en el estudio de la fractura por fatiga en la ZAC de los aceros microaleados de alto límite elástico

Abstract

Various applications have been described in the literaturefor the High-Strength and Low-Alloy steels (HSLA) industry, analysing their use both in industrial and marine equipmentand machines and in structures that require appropriate resilience values and toughness at low temperatures. Forsuccessful operation under conditions as large structures under extreme service conditions, it is essential to ensure the propertoughness both in base metal (USITEN 355 0.5 Ni Grade I steel)and in the Heat affected zone of the Weld (HAZ). This researchcarries out Crack Tip Opening Displacement (CTOD) tests, showing, in this article, the first part of the test correspondingto fatigue pre-cracking and a summary table of the results offracture toughness, to guarantee that, under the conditionswhich exist in welding, both the fatigue fracture values and the fracture toughness are acceptable by the applicable standards.