The structure of sintered porous sheets consists of the metallic framework of sintered powder grains and the spatial network of intercommunicating pores. The specific structure has an influence on the behaviour of different outer solicitations and plastic deformations. So, the specific structure of sintered porous sheets imposes special bending methods (for obtaining parts under the form of tubes) where the effect of the tensile stress must be relieved. The paper presents experimental results at planetary rolling, and bending methods with elastic cylinder to sintered porous sheets, considered in literature as bending methods "without stretching". Deformation of the porous sheet is local, successive and uniform. These conditions result in improving the deformation capacity, that is the deformability by bending the sintered porous sheets. The preliminary results obtained with regard to the influence of porosity and of certain technological parameters and fracture upon the curvature relative radius justify the need to approach the study and research of sintered porous materials in this field. The conclusions on the fracture mechanism and character based on the scanning electronic microscopy studies are presented.
展开▼
