Journal of Iron and Steel Research International vol:18 pages:893-897
6th International Conference on High Strength Low Alloy Steels (HSLA Steels 2011) location:Beijing, PEOPLES R CHINA, date:31 May - 2 June 2011
Recently the automotive industry has been confronted with the phenomenon of delayed fracture. This phenomenon was not relevant in earlier years since the strength level of the steels was generally below a critical level. However, delayed fracture is not necessarily related to an absolute strength value but rather to microstructural features as well as pre-existing micro-damage in the material that are likely to occur in ultrahigh strength steels. Niobium microalloying in combination with appropriate processing can effectively help to improve the resistance against delayed fracturing in such steels. The paper outlines a strategy how to achieve this based on microstructural control and hydrogen trapping.