The Organization And Performance Prediction Of TA15 Titanium Alloy Heat Spinning Based On The Plane Compression Model

Power spinning have a wide range of applications in aviation, aerospace, weapons industry and other important areas, because of its high utilization ratio, high forming precision, excellent performance, the required tonnage of small equipment and low cost, etc. The forming of thin-walled axially symmetrical titanium alloy components is more and more used by spinning, but now the research of titanium alloy heat spinning technology is focused on how to improve the forming accuracy, however the research of the control of spinning performance and organization is seldom, in order to achieve precise control of titanium spinning, the related research is extremely needed to be carried out.This paper first analyzes the mechanism of spinning deformation, then the hot spinning experiment of TA15 titanium alloy thin-walled axially symmetrical component is finished in RLE-800 CNC spinning machine, and evolution law of organization in spinning process is analysed. The research shows that: in spinning process the axial elongation and radial compression is main deformation, the deformation of circle direction is seldom, so the spinning deformation can be approximately as plane deformation.Secondly, the Instron-5500R electronic universal testing machine is used for the heat compression experiment of TA15 titanium alloys by the self-made mould. The microstructure of the heat compression and hot spinning is observed by the optical microscope and the micro-hardness is also measured, meanwhile the size of primaryαphase and recrystallization volume fraction of microstructure is quantitatively analyed by the Image-Pro Plus 6.0 image analysis software. The results show that: the size of the primaryαphase decreases when the deformation temperature, strain rates or strain increases; the volume fraction of recrystallization increases when the deformation temperature, strain rates or strain increases; the microhardness continuously declines when the deformation temperature increases, its value constantly increases when the strain and the strain rate increases.At the same time, the performance and organization of plane hot compression and hot spinning experiment is comparatively studied, The research shows that: in the same deformation conditions, the microstructure of two experiment methods is similar, both the error of micro parameters between plane hot compression and hot spinning experiment is within 15%.Based on BP neural network by the MATLAB toolbox, the neural network forecast model of the organization and performance of TA15 titanium alloy heat spinning deformation is established. This model has 3 layers'neural network model (network structure 3×7×3, the deformation temperature, deformation rate and deformation degree is as the input of the network, the size of the primaryαphase, volume fraction of recrystallization, and micro-hardness are as the output of the network). The analysis shows that prediction error of the model is less than 14%, it can be used as forecast model of the evolution of performance and organization in titanium alloy spinning process.