Research On Controled And Used Of The Non-uniform Deformation In Forging Process

The non-uniform deformation will be produced because of the friction factors in metal forging process,which is an important impact on structure property after the material forming.Therefore,in the field of plastic processing,the non-uniform deformation is always very important research subject.In this paper,based on the basic principles of plastic forming,forging stock shape design into a continuous variable cross-section body for improving the forging process of non-uniform deformation.The principal works in the thesis are as follows:Some process technology parameters,such as geometry parameters of H/D,cone angleα,the friction conditions and material properties,are studied and optimum parameters which get better control the non-uniform deformation are obtained.Using the method of the grid,observed the metal deformation and flow of the state of the variable cross-section sample after deformation.The 1A85 pure aluminum continuous variable cross-section body carries on the cycle extrusion,research its structure, mechanical properties using SEM and so on.The results show that continuous variable cross-section sample is upsetting,along the high-level to micro-deformation metal deformation and radial flow associated with area,the area is lesser,deformation is more,Present continuously and evenly deformation for cylinder by the frustum of a cone.Deformation does not appear the drum-shaped phenomenon,also does not appear compression instability or interface composite phenomenon;found that various units level thickness change rule is big for the first rate of change,reduces gradually downward,grid from the longitudinal profile changes can see the same rule.The 1A85 pure aluminum of Macro-columnar structure deformation after one cycle has been significantly refined and become more uniform, after pressing 8 times,the average grain size is 750nm.Hardness enhance with the increase of cycle deforming times and enhanced about 1 time,Longitudinal profile along the radial and axial differences in the various parts of the hardness with the increase in the number of multi-cycle decreases.