A methodology for assessing short fatigue crack growth in DCI materials affected by intergranular embrittlement at temperatures nearby 400 °C. (February 2022)

• Record Type: Journal Article
• Authors: Trelles, Elena Garcia; Schweizer, Christoph
• Is Part Of: International journal of fatigue. Volume 155(2022)
• Publication Date: 2022-02
• Subjects: Thermomechanical fatigue -- Intergranular embrittlement -- Ductile cast iron -- Lifetime assessment -- Fatigue short crack growth; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2021.106592
• Languages: English
• ISSNs: 0142-1123

Abstract

Abstract: A crack growth model for assessing the lifetime and short fatigue crack growth of ductile cast iron materials is proposed. The model bases on the assumption that the crack advance per cycle correlates with the cyclic crack tip opening displacement. Intergranular embrittlement at medium temperatures is accounted for as a temperature and strain rate dependent crack accelerating mechanism. The model is calibrated and successfully applied to predict temperature dependent fatigue lifetime and short crack growth of a ductile cast iron material. Highlights: A short crack growth model is proposed for assessing the fatigue lifetime of DCIs. The proposed short crack growth model accounts for intergranular embrittlement (IE). IE is modeled as crack acceleration activated at temperatures nearby 400 °C. The model is validated in terms of fatigue lifetime and short fatigue crack growth.