Failure behavior of the ceramic thin-walled cylindrical shell under the hydrostatic pressure

Due to the ceramic with high compressive strength and superior corrosion resistance, using ceramic as the parent material of underwater pressure shell is a reliable choice. The failure behaviors and ultimate strength of the 99% alumina ceramic cylindrical shells with sealed ends under the hydrostatic pressure are systematically investigated by means of theoretical, experimental and numerical methods. The theoretical prediction of two possible failure modes, including both the circumferential buckling and strength failure, of the cylindrical shell is firstly made. Then, the hydrostatic tests are carried out for the ceramic cylindrical shell specimens with a constant thickness-radius ratio (t/R = 0.07) and different length-radius ratios (L/R = 3, 4, 5, 6), and the ultimate pressures of the corresponding specimens are acquired. Good agreement among the theoretical, numerical and experimental results has been obtained. Moreover, the results show that the structural tolerance pressure can be effectively improved by increasing the thick-radius ratio or decreasing the length-radius ratio. Meanwhile, the conversion of two possible failure modes of the 99% alumina ceramic has been clearly revealed through changing the geometrical parameters of the cylindrical shell. This work provides the engineering guidance for the underwater pressure-resistant structural design.