Hi All
do decrease part of a cylindrical steel, we use backward extrusion (not hollow ) , but I notice that in the region of diameter change and also further ahead ( I mean where we have only the lower extruded diameter , that to me seems that there should be less contact and friction ), the material is rubbed away, and I see a lot of extrusion lines visible, like the material was too much in contact with the dies, how is this possible and where should I search the cause ? is it the deformation velocity ? lubrication or deformation ratio ?
any article related is so welcomed
do decrease part of a cylindrical steel, we use backward extrusion (not hollow ) , but I notice that in the region of diameter change and also further ahead ( I mean where we have only the lower extruded diameter , that to me seems that there should be less contact and friction ), the material is rubbed away, and I see a lot of extrusion lines visible, like the material was too much in contact with the dies, how is this possible and where should I search the cause ? is it the deformation velocity ? lubrication or deformation ratio ?
any article related is so welcomed