Stress Intensity at the Initiation of Instability by R Curve


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The life expectancy or failure of aerospace pressure vessels is evaluated by the critical stress intensity determined by the crack growth resistance curve of a material. Load versus crack mouth opening displacement data is generated from the Compact Tension specimens made from the weld joints of maraging steel rocket motor segments. The steps involved to generate critical stress intensity factor is explained. A power law is adopted to model the crack extension in terms of stress intensity factor and determine the maximum failure load of weld specimens. Maximum failure loads of CT specimens obtained by test and analysis are presented.



Edited by:

K.R. Balasubramanian, S.P. Sivapirakasam and R. Anand




S. Sundaresan and B. Nageswara Rao, "Stress Intensity at the Initiation of Instability by R Curve", Applied Mechanics and Materials, Vols. 592-594, pp. 1160-1164, 2014

Online since:

July 2014




* - Corresponding Author

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