PSI - Issue 2_A

Marco Rocchini et al. / Procedia Structural Integrity 2 (2016) 879–886 M. Rocchini et al./ Structural Integrity Procedia 00 (2016) 000–000

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6. Conclusion The influence of inelastic (plastic and creep) strain/damage on the subsequent fatigue crack growth FCG and fracture toughness behaviour of 316H stainless steel has been examined. Creep damage was globally introduced into a 8% pre-compressed 316H stainless steel. Half sized compact tension samples have been extracted to perform FCG and fracture toughness ( J IC ) tests at room temperature. The results have been compared to previously obtained data on this GCD material and from as-received, pre-compressed and locally creep damage material, all of which were performed on standard sized samples. The results have shown that the plastic pre-compression and tensile creep pre-strain have insignificant effects on the fatigue crack growth behaviour of the material at room temperature. However, inelastic deformation and damage has resulted in reduced fracture toughness, which is related to the reduction in tensile ductility of the pre-strained materials. Acknowledgments The authors would like to thank Dr Ali Mehmanparast for the provision of the experimental data on standard size C(T) specimens employed in this work. This paper is published with permission from EDF Energy. References Albertini, C., Montagnani M., 1990, Strain-rate dependent of residual strength and ductility of AISI 316 stainless steel after creep, fatigue and irradiation, Res Mechanica 30(4), 361-375. ASTM, E647-08 : Standard Test Method for Measurement of Fatigue Crack Growth Rates. ASTM, E1820-15 : Standard Test Method for Measurement of Fracture Toughness. Gan, D., 1982. Tensile and fracture properties of type 316H stainless steel after creep, Metallurgical and Material Transaction A 13(12) 2155-2163. ISO, 12135-2002: Metallic materials : unified method of test for the quantification of quasistatic fracture toughness. Mehmanparast A., Davies C.M., Dean D.W., Nikbin K.M., 2010. Compressive pre-compression effects on the creep and crack growth behaviour of 316H stainless steel, in ASME PVP 18-22 July 2010, Proceeding of the ASME Pressure Vessels and Piping division, Bellevue, Washington, USA. Mehmanparast, A., 2012. The influence of inelastic damage on creep, fatigue and fracture toughness, PhD thesis, Imperial College London. Mehmanparast, A., Davies, C.M., Dean, D.W., Nikbin, K.M., 2013. The influence of inelastic damage and tensile deformation on creep crack growth behaviour of type 316H stainless steel”, in ASME PVP 14-18 July 2013, Proceeding of the ASME Pressure Vessels and Piping division, Paris, France. Mehmanparast, A., Davies, C.M., Dean, D.W., Nikbin, K.M., 2013. The influence of pre-compression on the creep deformation and failure behaviour of type 316H stainless steel, Engineering Fracture Mechanics 110, 52-67.