Issue 48

S.C.S.P. Kumar Krovvidi et alii, Frattura ed Integrità Strutturale, 48 (2019) 577-584; DOI: 10.3221/IGF-ESIS.48.56 583 Figure 10 : The stabilized hysteresis loop for ± 0.4% strain amplitude with and without hold. N f (continuous cycling: ± 0.4%) N f (1 minute tensile hold: ± 0.4%) Amount of stress relaxed at half life 2060 1735 9 MPa Table 4 : Comparison of creep-fatigue life with continuous cycling C ONCLUSIONS ased on the investigation of low cycle fatigue and creep-fatigue interaction tests on SS316Ti at 823 K, following conclusions can be drawn: 1. The material showed significant cyclic hardening followed by saturation and final fracture during cyclic loading. 2. The fatigue life decreased with increase in strain amplitude. 3. Dynamic strain ageing was observed in the material during initial cycles which disappeared with further cycling. 4. The creep-fatigue interaction life was found to be lower than that in pure fatigue experiment. 5. The tensile and fatigue data generated will be useful for the design of SS316Ti bellows. R EFERENCES [1] Fontana M. G. (1987). Corrosion Engineering, McGraw Hill Book Company, Singapore. [2] Kumar Krovvidi S.C.S.P., Padmakumar G. and Bhaduri A.K. (2017). Experience of various materials for design and manufacture of bellows for nuclear industry, J. Advance Mater. Proc., 2 pp. 156-161. DOI: 10.5185/amp.2017/305. [3] Standards of Expansion Joint Manufacturer’s Association (EJMA) – 10 th Edition, 2016. [4] Design and construction rules for mechanical components for nuclear installations RCC-MRx, 2012. [5] ASME Boiler and pressure vessel code, section-III, 2017. [6] Srinivasan V.S., Valsan M., Rao K.B.S., Mannan S.L. and Raj B. (2003). Low cycle fatigue and creep–fatigue interaction behavior of 316L(N) stainless steel and life prediction by artificial neural network approach, Int. J. Fatigue, 25 pp. 1327- 1338. DOI: 10.1016/S0142-1123(03)00064-1. [7] Rao K.B.S., Sandhya R. and Mannan S.L. (1993). Creep-fatigue interaction behaviour of type 308 stainless steel weld metal and type 304 stainless steel base metal, Int. J. Fatigue 15 pp. 221-229. DOI: 10.1016/0142-1123(93)90180-X. B