Optimized thick-wall cylinders by virtue of Poisson’s ratio selection Part 1: Isochoric pressure application

Abstract

The principal stress distributions in thick-wallcylinders due to variation in the Poisson'sratio are predicted using analytical and finite element methods. Analyses of appropriate brittle and ductile failure criteria show that under the isochoricpressure conditions investigated that auextic (i.e. those possessing a negative Poisson'sratio) materials act as stress concentrators; hence they are predicted to fail before their conventional (i.e. possessing a positive Poisson'sratio) material counterparts. The key finding of the work presented shows that for constrained thick-wallcylinders the maximum tensile principal stress can vanish at a particular Poisson'sratio and aspect ratio. This phenomenon is exploited in order to present an optimized design criterion for thick-wallcylinders. Moreover, via the use of a cogent finite element model, this criterion is also shown to be applicable for the design of micro-porous materials.