The leakage criterions of thin-wall pressure vessels,materials of missile and spacecraft

This paper presents the development of three leadage criterions to predict fracture in thin-wall pressure vessels, materials of missile and spaceraft. Experimental results show that the criterions are successful.I. Notation P internal pressure kg/mm² - _b critical stress kg/mm² - t wall thickness mm - r internal radius mm - t _o wall thickness at crack tip mm - r _o internal radius at crack tip mm - _B yield strength kg/mm² - _H circumferential stress at the yield tange of the crack tip kg/mm² - n rate of strain gardening - 2c length of surface-crack mm - a depth of surface-crack mm - L length of testing piece mm - K, C, B, aA constant