PSI - Issue 19

R.B. Kalombo et al. / Procedia Structural Integrity 19 (2019) 688–697 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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strands or between the cable and the suspension clamp. Dimples were observed, showing that the failure progressed through the cable strand until the applied load caused the remaining section to fail by ductile fracture (Fig. 7).

a

b

Fretting mark.

c

d

Fretting mark.

Fig. 7. Fracture surface of strands showing the crack initiation at the fretting mark and dimples for the two cables (a, b) AAC Orchid Aluminium 1350 and (c, d) AAAC 823 MCM Aluminium 1120. 5. Conclusions This experimental study presents the fatigue performance of two cables made of pure aluminium 1350 and 1120 named AAC Orchid and AAAC 1120. Fatigue tests were performed on the two cables stretched with the same value of the H/w parameter. Two S-N curves were generated and failure analyses were established on a macroscopic and a microscopic scale. Based on the results and discussions presented, the following conclusions can be drawn: ❖ The two cables present a good fatigue performance compared to the CSBL. ❖ For the limited number of data here produced cables made of aluminium 1120 showed a longer fatigue life than those made of aluminium1350 for the same stress amplitude level. ❖ Transmission lines using cables made of aluminium 1120 could, in principle, be stretched at a higher EDS

values than the AAC ones and still be safe against aeolian vibration. ❖ Similar fracture behaviours were observed for both types of cable. Acknowledgements

The authors would like to acknowledge the support of Taesa, Transmissora Brasileira de Energia (TBE), ATE II Transmissora de Energia, ATE III Transmissora de Energia, Brasnorte Transmissora de Energia, Empresa