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applied fracture mechanics

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Fracture Mechanics Based Models of Structural and Contact FatigueFracture Mechanics Based Models of Structural and Contact Fatigue 91530.11max(k 1)/k 0x/L 00.10.090.080.070.060.050 10 20 30 40Figure 1. Illustration of the growth of the initially randomly distributed normal stress intensity factor k 1with time N as initially unit length fatigue cracks grow (after Tallian, Hoeprich, and Kudish [7]).Reprinted with permission from the STLE.To determine fatigue life N of a contact for the given survival probability P(N) =P ∗ , it isnecessary to solve the equationp m (N) =P ∗ . (17)2.7. Fatigue life calculationSuppose the material failure occurs at point (x, y, z) with the probability 1 − P(N). Thatactually determines the point where in (16) the minimum over the material volume V isreached. Therefore, at this point in (16), the operation of minimum over the material volumeV can be dropped. By solving (16) and (17), one getsN = {( n 2 − 1)g 0[ max k 10] n } −1 {exp[(1 − n−∞

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