PSI - Issue 14

Sachin Bandgar et al. / Procedia Structural Integrity 14 (2019) 330–336 Sachin V Bandgar/ Structural Integrity Procedia 00 (2018) 000–000

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R=0.1 in case of steel A and steel B respectively.  In the case of intercept 'C', it was found that the decrease in intercept 'C' when load ratio was increase to 0.5 is significant in case of steel A than steel B.  Limiting values of K max and ∆K for various crack growth rates has been found for steel A and steel B.  From fractography study, it was found that secondary cracks are predominant in steel A at a load ratio of R=0.1 as compared to R=0.5. However for steel B, secondary cracks were found at both the loadratios.  Number of cycles for a given crack length was found to be lesser for R=0.1 than that of R=0.5 for both steel A and steel B.  Fatigue crack growth rate was found to be higher for steel A than steel B at both load ratio R=0.1 and0.5. References Aung, Htay, 2007, An analysis of the study of mechanical properties and microstructural relationship of HSLA steels used in ship hulls,World Maritime University Dissertations190 Campbell F.C, 2012, Fatigue and fracture- Understanding the basics, Published by ASM International, Ohio, USA Czyryca Ernest J, 1990, Development of low-carbon, copper-strengthened HSLA steel plate for naval ship construction. David Taylor Research Center, Report DTRC-SME-90/21. Czyryca EJ, Vassilaors MMG,1993, Advances in low carbon, high strength ferrous alloys, Naval SurfaceWarfare Center, Report – CARDEROCKDIV-SME-92/64. Kim B.C, Lee S, Lee D.Y,Kim N.J, 1991,In situ fracture observations on tempered martensite embrittlement in an AlSl 4340 steel , Metallurgical Transactions A, Volume 22, Issue 8,1889–1892 Kwai S.Chan, Yi-MingPan, David Davidson and R. CraigMcClung, 1997,Fatigue crack growth mechanisms in HSLA-80 steels, Materials Science and Engineering, Volume 22, Issue 1, 1-8 Sadananda K, Vasudevan, A.K, 2003, Fatigue Crack growth mechanisms in Steels, International Journal of Fatigue Vol.25 Iss.9-11, 899-914. Sadananda K, Vasudevan, A.K, 2004, Crack tip driving forces and crack growth representation under fatigue, International Journal of Fatigue, Vol.26, Issue 1,39-47 ASTM E647-15e1, 2015, Standard Test Method for Measurement of Fatigue Crack Growth Rates, ASTM International, PA, USA.