Fatigue damage mechanisms

O Brien, T.K., Characterization of Delamination Onset and Growth in a Composite Laminate in Damage in Composite Materials, ASTM STP 775, p. 140-167,1982 Poursartip, A. Ashby, M. F., Beaumont P.W.R., The Fatigue Damage Mechanics of Fibrous Laminates in Proceedings of the European Workshop on Nondestructive Evaluation of Polymers and Polymer Matrix Composites, Polymer NDE (edited by Khg. Ashbee), Technomic Publishing, p. 250-260, 1984... 

It is important to note that the uniaxial loading of an off-axis plate generates a local (inherent) multiaxial stress state. It is therefore worth mentioning the investigations by Kawai and coworkers for the description of the off-axis fatigue behavior of UD and woven reinforced laminates [61,71,72] and their fatigue damage mechanics model [61]. The model is based on the nondimensional effective stress concept, which is the square root of the Tsai—Hill polynomial. 

S. S. Manson, Avoidance, Control, and Repair of Fatigue Damage, Metal Fatigue Damage-Mechanism Detection, Avoidance and Repair, ASTM STP495, American Society for Testing and Materials, Philadelphia, Pa., 1970, p. 254. 

Design and alloy development studies require mean as well as minimum (lower bound) Basquin relationships and statistics on the distribution of Ao versus Nf data. This distribution depends on the fatigue damage mechanism. Most... 

A Conceptual Framework for the Interpretation of Fatigue Damage Mechanisms in Composite Materials, J. of Comp. Technology Research, 7 (1985) 2, p. 25-29... 

Wells, C.H. Sullivan, C.P. Gill, M. Mechanisms of fatigue in the creep range. In Metal Fatigue Damage—Mechanism, Detection, Avoidance, and Repair Manson, S.S., Ed., ASTM Philadelphia, 1971 61-122. 

Turbine rotating blades cannot be field-repaired if they are cracked. If one or two blades are damaged mechanically, the manufacturer may recommend field repair or replacement of the damaged blades. However, if several blades are fatigue cracked, it is recommended that the entire set be replaced, since the remaining blades have been exposed to the same operating conditions and, therefore, have little fatigue life left. 

Environments. Among the environmental factors that can shorten life under thermal fatigue conditions are surface decarburization, oxidation, and carburization. The last can be detrimental because it is likely to reduce both hot strength and ductility at the same time. The usual failure mechanism of heat-resistant alloy fixtures in carburizing furnaces is by thermal fatigue damage, evidenced by a prominent network of deep cracks. 

Jeng, S.M., Yang, J.M. and Aksoy, S. (1992). Damage mechanisms of SCS-6/Ti-6Al-4V composites under thermal-mechanical fatigue. Mater. Sci. Eng. A 156, 117-124. 

Martin, R.B. and Burr, D.B. (1982) A hypothetical mechanism for the stimulation of osteonal remodeling by fatigue damage. Journal of Biomechanics 15 137-139... 

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