Study On The Stability Of Surface Turning Finishing Process Of Titanium Alloy Wire Based On Process Damping

Aviation fasteners have strict requirements for the surface quality,physical properties and mechanical properties of the preparation of blanks,and titanium alloys are widely used in the manufacture of aviation fasteners due to their own excellent characteristics.In engineering practice,the preparation blank of aviation fasteners is often in the form of titanium alloy wire disc,which needs to be surface finished to improve surface quality.Titanium alloy is a difficult material to machine,coupled with the slender structure characteristics of titanium alloy wire disc,so that unstable cutting chatter is easy to occur during processing,which affects the surface quality of titanium alloy wire after processing.In order to improve the machining stability of the centerless lathe cutting titanium alloy wire coil,considering the influence of process damping effect,the multi-degree-of-freedom coupling flutter dynamics model of the centerless lathe cutting system was established,and the stability analysis and stability influencing factors of the centerless lathe cutting system were carried out to obtain a stable machinable parameter group,and experimental verification was carried out to avoid the occurrence of cutting chatter.The main contents of the project research are as follows:(1)By analyzing the structural composition and force of the centerless lathe cutting system,considering the low-speed cutting characteristics of titanium alloy wire disc,the multi-degree-of-freedom coupling flutter dynamic model of the centerless lathe cutting system considering the process damping effect and the process damping effect without considering the process damping effect are established,and the mathematical expression results of the spindle speed n and the limit cutting depth AP are derived.(2)The system modal parameters were obtained by the finite element modal analysis of the centerless lathe cutting system,and the stability leaf lobe diagram of the centerless lathe cutting system was drawn by MATLAB software based on the mathematical expression of the spindle speed n and the limit cutting depth a_pfor stability analysis,and the stable machinable parameter group was obtained.At the same time,the stable lobe diagram considering the process damping effect and the process damping effect without considering the process damping effect were compared and analyzed,and the stable processable parameter area of the centerless lathe was significantly increased by considering the process damping effect.(3)By analyzing the influence of tool structure parameters on the stability of centerless lathe cutting system,the stability blade diagram of each tool structure parameter under different values is drawn respectively,and the tool structure parameter selection domain is obtained,which guides the structural design optimization of the tool and provides a theoretical reference for tool selection in the existing tool library before finishing machining.(4)By analyzing the influence of system structural parameters on the stability of the cutting system of centerless lathe,the stability lobe diagrams of each system structural parameters under different values are drawn respectively,and the selection domain of system structural parameters is obtained,so as to guide the structural optimization of centerless lathe.(5)By building a centerless lathe finishing TB9 wire test platform to verify the theoretical analysis results,numerical analysis and time-frequency analysis of vibration signals respectively,and comparative analysis of the surface roughness value and surface state of the wire under different cutting states,the reliability of the multi-degree-of-freedom coupling flutter dynamic model of the centerless lathe cutting system considering the process damping effect can be judged.