Crack Paths 2009

Figure 2- Specimens A and B

The results of the neutron diffraction measurements were transformed from strains to

stresses. The residual stress profiles through the thickness of specimens 1 and 2 in the

peened region are shown in figures 3 and 4. In order to ensure the accuracy of the

readings, strains at the required positions in each specimen was measured, and then the

specimen was taken out of the set up and put back in, this time the reverse side facing

the beam. Figures 4 and 5 show that a good agreement is observed between the two

readings for each specimen.

Specimen1 - longitudinal stress profile

200

100

0

)

e s s ( M P a

-5

-4

-3

-2

-1

0

1

2

3

4

5

-100

-200

s t r

-300

specimen1

-400

specimen1 - reversed

-500

distance from centre (mm)

Figure 3- Residual stress distribution profile in specimen 1 at the centre of the laser peened region.

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