Cyclic Fatigue Crack Propagation

M. J. Reece, F. Guiu, and M. F. R. Sammur, Cyclic Fatigue Crack Propagation in Alumina under Direct Tension-Compression Loading, J. Am. Ceram. Soc., 72[2], 348-352 (1990). 

Dauskardt, R.K., Yu, W., and Ritchie, R.O. (1997) Mechanism of cyclic fatigue crack propagation in a flne grained alumina ceramic the role of crack closure. Fatigue Fract. Eng. Mater. Struct., 20, 1453-1466. 

Liu H-Y, Wang G, Mai Y-W (2012) Cyclic fatigue crack propagation of nanoparticle modified epoxy. Compos Sci Technol 72(13) 1530-1538... 

Fig. 7.26 a Cyclic fatigue-crack propagation rates, da/dN as a function of the applied stress-intensity range AK for SiC,-reinforced alumina. Data obtained for long cracks on C(T) samples in a room-air environment at 50 Hz with a constant load ratio (R = Kmin Vniax) of 0.1 [5]. With kind permission of John Wiley and Sons... 

Ritchie, R.O. et al.. Cyclic fatigue-crack propagation, stress-corrosion, and fracture-toughness behavior in pyrolytic carbon-coated graphite for prosthetic heart valve applications. JBiomed Mater Res, 1990. 24(2) p. 189-06. 

Several theories have been proposed to explain the corrosion-fatigue phenomena. One is that cyclic stressing causes repeated rupture of protective coatings. Corrosion-fatigue cracks propagate as the coating is successively reformed and ruptured along a plane. 

Data on fatigue crack propagation are gathered by cyclically loading specimens containing a sharp crack like that shown in Fig. 15.7. We define... 

Barsom, J. M., Effect of cyclic stress waveform on corrosion fatigue crack propagation... 

Figure 6.51 Corrosion fatigue crack propagation rate (da/dN) as a function of the cyclic crack tip stress intensity range (AK) (Phull)5...

A further development of this procedure is fatigue crack propagation (FCP) experiments in the presence of a stress cracking environment. While in the fracture mechanics test methods described above the specimen is under constant load, in a FCP experiment the specimen is tested under cyclic loading conditions in the presence of a sensitizing medium. 

In the literature on fatigue crack propagation in metals and, later, in polymers it has been well documented that fracture surfaces can exhibit ripple markings which are due to the cyclic loading process. 

Several authors have demonstrated a close correlation between the value of the toughness measured in a single deformation and the fatigue crack propagation (FCP) rates measured in cyclic loading at lower stresses Hertzberg and Manson have produced a useful summary of this area (32). The FCP rates, Rf, may be expressed by the Paris equation which contains two material parameters, A and m ... 

Fatigue crack propagation because of cyclic and uneven loading was also a contributing factor. The use of steels of higher toughness with intrinsic weathering resistance has been advanced as a remedial measure. 

Cyclic crack-growth experiments were performed in SiC whisker-reinforced Al203-SiC ceramic composites. The fatigue-crack propagation rate, da/dN, of long cracks (in excess of 3 mm) has indicated a power law-dependent function of the applied-stress intensity according to the Paris Law Eq. (7.9). The values of C and... 

To characterize the cyclic crack growth resistance of both neat resins and laminates, fatigue crack propagation (FCP) experiments under Mode I conditions were performed in laboratory air (23 C/50%r.h.) using a computer controlled servohydraulic fatigue testing machine. In the case of neat resins, compact-type (CT) specimens with a width of 50 mm, a hight-to-width ratio of 0.6, and a nominal thickness of 4 mm were used. For composite laminates double cantilever beam specimens (125 x 20 x 8 inm ) were employed. FCP tests were conducted at 10 Hz. The applied waveform was sinusoidal with a constant load amplitude and a minimum-to-maximum load ratio, R, of 0.1. 

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