Issue 78

V. Pisarev et alii, Fracture and Structural Integrity, 78 (2026) 96-117; DOI: 10.3221/IGF-ESIS.78.06

D ETERMINATION OF PRINCIPAL RESIDUAL STRESS COMPONENTS

T

he configuration of interferograms, shown in Fig. 3–6, provides a strong foundation to apply the approach developed in works [1, 2] for determination of principal residual stress component 1 σ and 2 σ , in direction u and v , respectively. Initial experimental information extracted from the fringe patterns and the calculated values of the principal residual stress components for all four investigated coupons are listed in Tab. 2.

Point/ Dimple

Distance from dimple center to probe hole center x / y , mm

u N  , fringes

v N  , fringes

1 σ , MPa

2 σ , MPa

Δ u , μ m

Δ v , μ m

Coupon Sp_55

–14.0 –12.0 –11.5

–9.5

–5.32 –4.56 –4.37 –2.85 +5.51

–5.61 +6.46 +6.08 +4.94 –1.14 –1.33 –4.18 –1.14 –5.51 +6.84 +5.32 +4.94 –6.08 –0.38 –0.76 –1.71 –5.13 +5.13 +8.36 +4.18 +7.60 +7.03 +3.04 –6.08

1 x = 1 y = 0

–142.0 –45.5 –44.5 –21.2 +108.2 +70.3 +44.5 +35.4

–119.3 +101.1 +94.5 +82.4 +19.7

1/D1 5/D2 7/D2 2/D1 6/D2 8/D2 4/D1 3/D1 1/D1 5/D2 7/D2 2/D1 6/D2 8/D2 4/D1 3/D1

+17.0 +16.0 +13.0

5 x = 5.1, 5 y = 0 7 x = 7.9, 7 y = 0 2 x = 8.0, 2 y = 0 6 x = 0, 6 y = 5.1 8 x = 0, 8 y = 7.9 4 x = 0, 4 y = 8.0 3 x = 0, 3 y = 10.0 5 x = 5.5, 5 y = 0 7 x = 7.5, 7 y = 0 2 x = 8.0, 2 y = 0 6 x = 0, 6 y = 5.5 8 x = 0, 8 y = 7.5 4 x = 0, 4 y = 8.0 3 x = 0, 3 y = 10.0 5 x = 5.8, 5 y = 0 5 x = 5.8, 5 y = 0 7 x = 7.2, 7 y = 0 2 x = 8.0, 2 y = 0 2 x = 8.0, 2 y = 0 6 x = 0, 6 y = 5.8 6 x = 0, 6 y = 5.8 8 x = 0, 8 y = 7.2 4 x = 0, 4 y = 8.0 3 x = 0, 3 y = 10.0 1 x = 1 y = 0 1 x = 1 y = 0 1 x = 1 y = 0

–7.5

–3.0 –3.5

+14.5 +10.0

+3.8

+2.0

0.0

+7.60 +2.09

+5.5 +5.5

+16.7

–3.0

–7.6

Coupon Sp_65

–24.0 –13.0

–14.5 +18.0 +14.0 +13.0

–9.12 –4.94 –3.61 –4.56 +6.65 +2.28 +2.09 +3.23 –4.56 –5.13 –3.04 –4.37 –3.80 –3.04 +9.12 +6.46 +3.42 +2.47 +1.90 –10.64

–238.0

–190.0 +106.1 +84.4 +68.7 +12.6 –22.2

–50.5 –34.4 –57.6

–9.5

–12.0 +17.5 +6.0 +5.5 +8.5 –28.0 –12.0 –13.5

–5.0 –1.0 –2.0 –4.5

+126.4 +33.4 +38.4 +55.1

+0.5

–10.6

Coupon Sp_75

1/D1

–13.5 +13.5 +22.0 +11.0 +20.0 +18.5 +8.0 –16.0

–267.4

–194.1

1_Back

–56.1

+72.8

5/D2

–42.5

+137.0

5_Back

–8.0

–31.3

+64.7

7/D2 2/D1

–11.5 –10.0

–32.3 –24.8

+127.0 +119.3

2_Back

–8.0

–40.4

+40.4

6/D2

+24.0 +17.0

+145.6

–56.6

6_Back

0.0

0.0

+137.5

+51.6

8/D2 4/D1

–1.0

–0.38

+9.0 +6.5 +5.0

+70.0 +52.5 +40.4

+19.2 +19.7 +15.2

0.0 0.0

0.0 0.0

3

Table 2: Experimental parameters and residual stress component values inside and outside of contact dimple.

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