PSI - Issue 19

S. Periane et al. / Procedia Structural Integrity 19 (2019) 415–422

422 8

S.Periane t al. / Structural Integrity Procedia 00 (2019) 00 – 000

(b)

1

2

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(c)

Fig. 10. Fractured surface of the sample machined under emulsion condition

Conclusion

The heat treatments such as HIP and AHT have highly decreased the presence of porosity and increased the hardness value of about 35% compared as built sample which is essentially criteria to perform fatigue test. Under dry condition induced sub surface damage leading to the source of crack initiation and propagation in the middle of the sample corresponding to the highest endurance value during the fatigue test. The cutting force in the dry condition is higher than in emulsion condition due to higher thermal load. The fatigue resistance is enhanced by the thermal history in turn it leads to a better surface finish compared to emulsion. In emulsion condition the thermal subsurface is removed leading to random crack initiation and propagation. Inspite of less cutting force compared to dry condition the roughness value is high of emulsion machined samples.

Acknowledgements

The authors would like to thank Dr.S.Vaudreuil and Dr. H.Chibane for fabrication support, Dr.J.CORMIER of (Futuroscope-Chasseneuil Cedex, France) and BODYCOTT enterprise for heat treatment support, Tool research center operators (CEROC, France) for machining support and Centre of study and research of elastomers materials engineer (CERMEL, France) for facilitating fatigue machine.

References

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