Effects of tensile load hold time on the fatigue and corrosion-fatigue behavior of turbine blade materials. (November 2021)

• Record Type: Journal Article
• Authors: Zhao, Gaole; Qi, Hongyu; Li, Shaolin; Yang, Xiaoguang; Shi, Duoqi
• Is Part Of: International journal of fatigue. Volume 152(2021)
• Publication Date: 2021-11
• Subjects: Fatigue-creep -- Lifetime -- Hold time -- Hot corrosion -- Fracture behavior; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2021.106448
• Languages: English
• ISSNs: 0142-1123

Abstract

Highlights: Effect of dwell time on fatigue and corrosion-fatigue is experimentally studied. Tensile load hold time significantly reduces fatigue life. Fatigue life of salt-coated samples is lower than that of the bare sample under 0 and 1 s holds. The crack initiation sites of bare samples shift from internal defect to surface with increasing hold times. Cracks in salt-coated samples are initiated on surface corrosion layer. Abstract: Fatigue-creep tests were carried out on bare and salt-coated of DZ125 superalloys samples at 850 °C. The fatigue lifetime of a corroded alloy was reduced by more than 80% as the hold time was increased to 120 s. However, the influence of hot corrosion on fatigue lifetime became weaker when the dwell time was further increased to 240 s. It was found that hot corrosion influences the lifetime of the alloy by controlling the crack initiation location. The cracks on salt-coated samples were initiated on the corrosion layer. These findings enable an accurate assessment of the hot-corrosion-induced fracture behavior of superalloys.