Analyzing the influence of fatigue crack rate on the peculiarities of heat dissipation at fracture

• Main Authors: Vshivkov, A., Iziumova, A., Zakharov, A., Shlyannikov, V., Plekhov, O.
• Format: Conference Proceeding
• Language: English
• Subjects: Biaxial loads; Crack initiation; Crack propagation; Crack tips; Dependence; Fatigue failure; Fracture mechanics; Heat flux; Heat transfer; Infrared detectors; Thermography; Titanium alloys; Titanium base alloys
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/1.5084436

This paper is concerned with an experimental study of heat dissipation from the fatigue crack tip in specimens under biaxial loading with a variable biaxial coefficient (0, 0.5, 1). Cruciform specimens were made from the Grade 2 titanium alloy. A contact heat flux sensor and the infrared thermography method were used for heat flux measurements. We have shown that heat dissipation caused by fatigue crack propagation under the Paris regime involves two stages both under uniaxial and biaxial loading conditions. The first stage is associated with the initiation and slow crack propagation regime (the crack rate is 10−7–10−5 m/cycle) and characterized by a nearly constant heat flux. The process of intensive heat dissipation begins at crack rates exceeding 10−5 m/cycle. A linear dependence of the heat flux on the rate of crack growth has been determined at both stages; however, at the first stage, the crack rate is proportional to the product of its length and heat flux.