PSI - Issue 2_B

Giovanni Meneghetti et al. / Procedia Structural Integrity 2 (2016) 2076–2083 G. Meneghetti / Structural Integrity Procedia 00 (2016) 000–000

2080

5

100

1000

(b)

(a)

Scatter bands:10% - 90% survival probabilities, from Meneghetti et al (2013)

Plain material k=17.2; T  =1.19; T N,  =20.0 Hole, R=8 mm: k=8.9; T  =1.18; T N,  =4.3 Stair case: broken, unbroken

Present work: plain material stair case: broken

unbroken

10

R=0.5 mm R=1 mm R=3 mm

k=5.8 T  =1.30 T N,  =4.5

Strain controlled U-notch, R=5 mm V-notch, R=3 mm

10 -1 Q [MJ/(m 3 ·cycle)] 1

 an [MPa]

Present work: plain material stair case: broken

Q k 2.11 A,50% 

3

cycle) 0.133MJ/(m 



unbroken

T 4.50 T 2.04 N,Q Q  

R=0.5 mm R=1 mm R=3 mm

100

70 10 2 10 3 10 4 10 5 10 6 10 7

10 -2

10 2

10 3 10 7 N f , number of cycles to failure 10 4 10 5 10 6

N f , number of cycles to failure

Fig. 4. Results of new fatigue tests in terms of a) applied net stress amplitude and b) specific heat loss per cycle. Scatter band is defined for 10% and 90% survival probabilities (from Meneghetti et al. (2013)).

(a)

(b)

(d)

10

(c)

230 220 210 200 190  a = 230 MPa  a = 220 MPa  a = 210 MPa  a =200 MPa  a =190 MPa  a =90 MPa  a =100 MPa  a =80 MPa  a =130 MPa  a =110 MPa  a =140 MPa  a =150 MPa  a =110 MPa  a =170 MPa V_45_R05_06 V_45_R05_07 V_45_R1_04 V_45_R1_05 V_45_R1_07 V_45_R1_08 V_45_R3_02 V_45_R3_04 V_45_R3_05

plain

1

R= 0.5 mm

0.1 Q [MJ/(m 3 cycle)]

R=1 mm

R=3 mm

0.01

0

0.25

0.5

0.75

1

N/N f

Fig. 5. Example of temperature maps for a) R=3 mm (  a =110 MPa, N f =122659, f=20 Hz), b) R=1 mm (  a =110 MPa, N f =90970, f=20 Hz), c) R=0.5 mm notch radius (  a =100 MPa, N f =198632, f=30 Hz) and d) Q versus N/N f trends, measured during the fatigue tests.