Research On Forming Quality Of Thin-walled Conical Parts With Continuously During Spinning

As an external carrier of aero-engine,the thin-wall casing is used for long-term under conditions of high temperature,high pressure and alternating load.Its material preparation and processing technology are complex,and the safety guarantee during service operation is also crucial.The thin-wall casing is a complex part with thin wall thickness and large diameter,which material is usually selected as superalloy,which makes it difficult to form and the deformation is difficult to control.There are residual stress inside the part after deformation,which becomes a hidden danger that restricts the service of the aero-engine.In this paper,the GH1140 superalloy variable-section tapered thin-wall casing is used as the research object,and it is formed by the spinning.The GH1140 superalloy sheet is select as blank,and the tensile test is performed at room temperature to obtain the true stress-true strain relationship which deformation rate is 0.05 mm/s,and the superalloy composition analysis is carried out.Based on Simufact.Forming finite element analysis software,the model of spinning formed the conical thin-wall casing is established,the test scheme is design by the hybrid orthogonal method.Based on the simulation of forming process and uploading of the rotary,the distribution law of the equivalent stress,the equivalent strain and the metal flow law on the upper surface of the casing are analyzed.The residual stress distribution law on the tapered axial section is analyzed by establishing a coordinate system.The forming process is divided into six sections,and the distribution law of tangential and axial residual stress are analyzed.And then,the effect of different process parameters on the spinning force is analyzed.The maximum of the spinning force is selected as the evaluation index of the forming quality,a functional equation between the process parameters and the spinning pressure is fitted.The wall thickness value in axial and circumferential section are output,and the variance of the thickness value is calculated to analyze the effect of process parameters on the wall thickness uniformity.The residual stress is the main cause of excessive deformation,so the XRD test is carried out to test the residual stress of casing and compared with the simulation results.The date error is small,which verifies the correctness of the model.The research results in this paper provide a theoretical basic for improving the forming of the thin-wall casing.