On the yield functionals in Lagrangian stress space of elasticplastic materials

OntheyieldfunctionalsinLagrangianstressspaceofelastic-plasticmaterialswithinternalconstraints，扶名福，陈良森，InthepresentpaperitisshownthattheelasticrangeinthesecondPiola-Kirchhoffstressspacecanbechoseninahyperplaneperpendiculartothedirectionrelatedtothesimpl