PLASTIC DEFORMATION BEHAVIOUR OF POROUS SINTERED STEELS

Five different sintered iron base materials with increasing alloy content were compressed in incremental steps to measure the deformation resistance and the density changes during plastic deformation. Of each material five initial density levels were investigated. Both, density increase and deformation resistance can mathematically be described by a parabola as depending on natural strain. Following Shima's and Oyna'es yield criterion for plastic deformation of porous materials an equivalent stress-equivalent strain curve is established for each material as the basic material law to model the deformation behaviour of porous sintered steels e.g. in surface rolling simulations.