Striation spacing

The propagation of a crack creates lines on the fracture surface, which lie parallel to the crack front, perpendicular to the direction of crack growth [6], Each incremental advance of the crack front results in the formation of a striation on the fracture surface (Fig. 4a). Temperature dependence of inter-striation spacing, measured from the fracture surface of the tested specimens is presented in Fig. 4b. 

DF1C velocities in RBMK TMO-1 samples, depending on temperature are 3-5 times lower than in CANDU pressure tube material. Crack growth in RBMK pressure tube material occurs at larger increments of the crack front. Striation spacing increases with increase in test temperature and appear to be larger in the specimens of the RBMK material than in the CANDU material. 

Figure 4. Striations on the DHC fracture surface (a) relationship between inter-striation spacing and temperature (b).

It can thus be concluded that during the so-called continuous mode of fatigue crack propagation there is no simple correlation between fatigue striation spacing and craze dimensions. 

Figure 9. Correlation between macroscopic growth increments per loading cycle and striation spacings as a function of aK in nylon 66 equilibrated to several moisture levels...

The shape of the active force-length curve (Fig. 6.3) is explained by the experimental observation that active muscle force varies with the amount of overlap between the thick and thin filaments within a sarcomere (see also Mechanism of Muscle Contraction in Sec. 6.5.2). The muscle force versus striation spacing curve given in Fig. 6.3c shows that there is minimal overlap of the thick and thin filaments at a sarcomere length of 3.5 pm, whereas at a length of about 2.0 pm there is... 

Haas (2001 a) Loser diffraction was employed to meosure the spacing of striations Spacing decreased with increasing spinning rote... 

Haas (2001b) Ophcal profilometery was employed for quantitative evaluation of striations Spacing decreased but amplitude remained constant when spinning rate increased Spacing was independent of the distance from the spinning center... 

Fig. 10.15 Comparison between measured crack growths and striation spacing observed on 2024-T3 aluminum alloy (modified from [26])...

Figure 10.18 [27] presents the empirical basis of the Bates and Clark finding. The exponent of two that appears in Eq. (10.23) induces to believe that striation spacing is somehow related to the Irwin plastic zone size (10.6) or to the crack tip opening displacement or CTOD that, as the plastic zone radius, is proportional to the square of the stress intensity factor K ... 

Yokobory, T., Sato, K. The effect of frequency on fatigue crack propagation rate and striation spacing in 2024—T3 aluminum alloy and SM-50 steel. Eng. Fract. Mech. 8, 81-88 (1976)... 

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