Effects of temperature and hold time on creep-fatigue crack-growth behavior of HAYNES ® 230 ® alloy

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2006-08, Vol.429 (1), p.1-10
• Main Authors: Lu, Y.L., Chen, L.J., Liaw, P.K., Wang, G.Y., Brooks, C.R., Thompson, S.A., Blust, J.W., Browning, P.F., Bhattacharya, A.K., Aurrecoechea, J.M., Klarstrom, D.L.
• Format: Article
• Language: English
• Subjects: Applied sciences; Creep; Exact sciences and technology; Fatigue crack-growth; Fractography; Fractures; Hold time effect; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Nickel-based superalloys; Oxide removal
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2005.07.039

The creep-fatigue crack-growth behavior of a HAYNES 230 superalloy was investigated at the temperatures of 649, 816 and 927 °C in laboratory air. The crack-growth experiments were conducted under the stress-intensity-factor-range or load-range control. Hold times in the range of 3 s to 5 h were imposed at the maximum load to study the influence of hold time on the crack-growth behavior. The fatigue and creep crack-propagation experiments were also performed as zero and infinite hold-time experiments, respectively. The crack-growth rate increased continuously with increasing the test temperature and/or hold time. The fracture surfaces and cross-sections through the fracture surfaces were examined. As the hold time increased, the fracture appearance changed from the transgranular to intergranular mode. At higher temperatures, this transgranular–intergranular transition occurred at a shorter hold time.