A physics-based model for evaluating hot compressive dwell effects on fatigue crack growth in 319 cast aluminum alloys

作者：Chen Xiang^*; Lados Diana A; Pettit Richard G; Dudzinski David

来源：International Journal of Fatigue, 2016, 90: 222-234.

DOI：10.1016/j.ijfatigue.2016.04.008

• Hot compressive dwell
• Fatigue crack growth
• Creep-fatigue
• Thermo-mechanical fatigue
• 319 Aluminum alloy

Fatigue crack growth under hot compressive dwell (HCD) conditions, a case of creep-fatigue occurring under compressive loading, is an important failure mode in high temperature environments. Creep induced tensile residual stresses gradually built up in the vicinity of the crack are considered to be a key factor contributing to crack growth under HCD conditions. To understand and quantify this effect, a simple physics-based model has been developed, in which the residual stress contributions associated with creep and plasticity are added to the elastic response of the material to predict crack growth under HCD conditions using Linear Elastic Fracture Mechanics (LEFM). Test of a cast 319 AI alloy has been conducted both for material characterization and under baseline and HCD conditions to evaluate the model. With HCD, the crack growth rate was increased on average by a factor of about 6, which is consistent with model predictions.

• 出版日期2016-9