Issue 55

F. Hamadouche et alii, Frattura ed Integrità Strutturale, 55 (2021) 228-240; DOI: 10.3221/IGF-ESIS.55.17

where its evolution increases each time L increases from 0.4 mm to 0.6 mm. For the third mode, the effect of the dimension of the singularity zone L on the evolution of K3 is very weak.

E FFECT OF THE LOAD

I

n this case, the effect of external forces on the evolution of the stress intensity factor SIF was studied. We always note that σ is the tensile force, and p is the pressure force of the pad on the specimen and this is the force that is created by the fretting phenomenon. This force is very small compared to the tensile force, that is why we have fixed the relation between the two forces by the following relation σ = 10 p, 10 times greater. The other parameters remain constant during the three materials tests (f = 1.0, H = 8 mm, L = 0 .6 mm and α = 45 °). The results obtained are shown in Fig. 12.

Aluminum

Steel

150

150

100

100

50

50

Ki/K0

0 Ki/K0

0

-50

-50

B

A

-100

-100

0

2

4

6

8

10

12

14

16

18

0

2

4

6

8

10 12 14 16 18

angular division n K1/K0 σ =100 K1/K0 σ =400 K1/K0 σ =700 K2/K0 σ =100 K2/K0 σ =400 K2/K0 σ =700 K3/K0 σ =100 K3/K0 σ =400 K3/K0 σ =700

angular division n K1/K0 σ =100 K1/K0 σ =400 K1/K0 σ =700 K2/K0 σ =100 K2/K0 σ =400 K2/K0 σ =700 K3/K0 σ =100 K3/K0 σ =400 K3/K0 σ =700

Brass

150

100

50

Ki/K0

0

-50

C

-100

0

2

4 8 10 12 14 16 18 angular division n K1/K0 σ=100 K1/K0 σ =400 K1/K0 σ=700 K2/K0 σ=100 K2/K0 σ=400 K2/K0 σ=700 K3/K0 σ=100 K3/K0 σ=400 K3/K0 σ=700 6

Figure 12: The factors Ki / K 0 as a function of the angular division n for different values of Load for the three materials (A) Steel, (B) Aluminum, and (C) Brass

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