Crack Paths 2009

50

-123410 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 2.2-40-weld 8 2

-20

-30

-40

-50

Fig. 9 The effect of pad-up parameter on crack path with the hole

3. P R E D I C T I O NOSFFINITIEE L E M E NA NTA L Y S I S

A 2D Finite element model of the sample was built then meshed with 4-node

quadrilateral elements in ABAQUS.The maximumtangential stress criterion was used

to predict the crack path. The SIGINI code was used to build a subroutine to input

example residual stress profiles into the models. The effect of hole position and residual

stress on crack paths was investigated (see Fig.10) with the same pad-up size at

2.8mmx40mm.For h  63m m, crack just get a little deviation from centre line, doesn’t

go into the hole, while

h  51m m, crack goes into the hole.

50

40

H51R30-with residual stress

H51R30-without residual stress

30

H63R30-with residual stress

20

H63R30-without residual stress

10

0

0 10 20 30 40 50 60 70 80 90

100 110 120 130 140 150 160

-10

-20

-30

-40

-50

m m

Fig.10 Predicted crack paths by F E A

661