ANALISI DEI CRITERI DI SNERVAMENTO PER MATERIALI POLIMERICI

Several experimental results show that the classical yield criteria (e.g. von Mises, Tresca-Guest) developed for traditional materials are not suitable for static design with polymers. In this paper, yield criteria proposed for polymers and different materials, characterised by the influence of hydrostatic component of stress field on yield strength and non symmetric behaviour, are presented and compared, by using experimental results taken from literature as well as obtained by the authors on an actual component.