PSI - Issue 37

6

R. Fernandes et al. / Procedia Structural Integrity 37 (2022) 462–468 R. Fernandes et al./ Structural Integrity Procedia 00 (2019) 000 – 000

467

 a,t , = , + , = 2 + 2

10

10

 a,t

 a,t (as-built)

1

 a,e

1

 a,e



0.1

 a,p

0.1

a,p

Strain amplitude (%)

Strain amplitude (%)

 a,p (as-built)

(a)

(b)

0.01

0.01

1.0E+01

1.0E+02

1.0E+03

1.0E+04

1.0E+05

1.0E+01

1.0E+02

1.0E+03

1.0E+04

1.0E+05

Number of reversals to failure, 2N f

Number of reversals to failure, 2N f

10

 a,t

 a,t (as-built)

1

 a,e

0.1

Strain amplitude (%)

 a,p

 a,p (as-built)

(c)

0.01

1.0E+01

1.0E+02

1.0E+03

1.0E+04

1.0E+05

Number of reversals to failure, 2N f

Fig. 5. Strain-life relationships of the AlSi10Mg aluminium alloy manufactured by laser-beam powder bed fusion for the different manufacturing routes: (a) as-built condition; (b) stress-relieved condition; and (c) T6 condition. 4. Conclusions This paper studied the cyclic deformation behaviour of AlSi10Mg aluminium alloy manufactured by laser-beam powder bed fusion for different processing states, namely in the as-built, stress-relieved, and T6 conditions. The cyclic deformation behaviour was analysed from low-cycle fatigue tests (R  = -1) performed under strain control mode for strain amplitudes in the range 0.2-1.5%. The following conclusions can be drawn:  The cyclic stress-strain response of the AlSi10Mg manufactured by laser-beam powder bed fusion is very sensitive to the heat treatment. The T6 condition exhibited a hardening behaviour, while the as-built and the stress-relieved conditions showed a mixed behaviour, i.e. hardening for higher strain amplitudes and softening for lower values;  The shape of the hysteresis loops was significantly different for the stress-relieved and the T6 conditions, when compared to the as-built state. The linear portion of the as-built case was considerably higher than that of the other two states. Moreover, the shape of the hysteresis loops did not significantly change during the tests for the as-built and T6 conditions;  Strain-life relationships evidenced different trends. The plastic strain component exhibited a bi-linear trend, on log-log scales, for the as-built and stress-relieved conditions, while the T6 condition could be fitted by a single linear function. Transition lives were much higher for the stress-relieved and T6 conditions.