Environmental Fatigue

As an alternative to vacuum, also noble, inert gases like argon can be used as a reference environment. A comparison between FCGR, da/dN, in air and in argon gas is offered in Fig. 16.6 for a low-alloyed carbon steel type A 508 Cl 3 fatigued at a frequency of 1 Hz [9]. Almost no difference can be observed. 

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Influence of Molecular Parameters on Environmental Fatigue Resistance. 126... 

Single Lap-Joint Specimen Test Results, is intended to give insight into the interpretation of the results from all the lap shear tests. At other points in ASTM Vol. 15.06 and in this chapter, reference is made to other standard tests that use shear-type specimens to explore moisture, and other environmental, fatigue, and creep effects in adhesive joints. 

Jones CJ et al. Environmental fatigue of reinforced plastics. Composites, 14, 288-293, 1983. Jones CJ et al. Environmental fatigue behaviour of reinforced plastics, Proc Royal Society of London, 396, 315-318, 1984. 

Jones CJ, Dickson RF, Adam T, Reiter H, Harris B. Environmental fatigue behavior of reinforced plastics. Compos 1983 14(3) 288-293. 

Typically, metal-bellows/gasket sealed high vacuum chambers are utilized for environmental fatigue experiments in inert or deleterious gaseous environments [4]. Such an apparatus is outside the scope of this review. 

Gasem, Z. and Gangloff, R. P., "Rate-Limiting Processes in Environmental Fatigue Crack Propagation in 7000-Series Aluminum Alloys," in Chemistry and Electrochemistry of Corrosion and Stress Corrosion Cracking A Symposium Honoring the Contributions of R.W. Staehle, R. H. Jones, Ed., TMS, Warrendale, PA, 2001, pp. 501-521. 

Slavik, D. C., Environmental Fatigue Crack Growth and Microscopic Danrage Mechanisms in AA2090, Ph.D. dissertation, University of Virginia, Charlottesville, VA, 1993. 

Jones, C.J. et aL (1983) Environmental fatigue of reinforced plastics. Composites 14, 288-93. 

Warner JS, Kim S, Gangloff RP (2007) Ionic inhibition of environmental fatigue crack growth in 1015-16, Key Engineering Materials 345-346, 989-994. 

Y. Shan, K. Liao (2001) Environmental fatigue of unidirectional glass-carbon fiber reinforced hybrid composite. Composites B 32, 355. 

Also the R ratio plays an important role in the FCGR, da/dN, in environmental fatigue as it does in conventional fatigue or non-environmental fatigue (see Sect. 11.4). This effect is shown in Fig. 16.23 for Ti-8Al-lMo-lV alloy tested in argon and 3.5 % NaCl solution [23]. But the R-ratio can have also another effect. In fact, by increasing the R-ratio SCC appears that otherwise would not occur. 

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