Crack Paths 2012

Both values are substituted into Richard’s criterion [1] for calculation of the kinking

angle ϕ as

2

ª

K K K K K K K § K

º

·

K

1 4 0 7 0 ,with 0 II II III = ° ⋅ − = ° ⋅ ¨ ¸ ¨ ¸ + + + + « » © ¹ ¬ ¼ B ϕ . (2) I I I I I I II I III « »

maxK I

K II

Figure 4 Out of phase mixed modes loading plotted as functions of contact position

In the subsequent loading step the calculated kinking angle ϕ is used to rotate the local

coordinate system xL, yL, see Figure 5, and the constant crack increment of the length of

0.03 m mis then imposed.

yL

xL

Crack growing due to rolling

contact loading and the

interference fit

y G

Initial crack

x G

Figure 5. Schemeof the crack configuration

For each crack increment also an equivalent stress intensity factor, see [1], is calculated

as

1010