Influence of combinatorial friction on bending forming of thick-walled tube

The bending forming process of thick-walled tube with filled medium was present ed,then the finite element model of the tube was established to simulate the bending form ing process.The influence of inside and outside friction coefficient on the stress,the strain,the forming load and the thickness of tube wall was investigated during the bending forming process of the tube.Numerical simulated results showed that friction is a impor tant process parameter of influencing on tube forming.The stress distribution and metal flow of the deformation zone were influenced by frictional force.The stress and the de forming force were both smaller and the uniformity of tube thickness was better.