钛合金材料超声滚压加工的仿真分析与实验研究

Simulation analysis and test research on ultrasonic rolling of titanium alloy materials

采用普通滚压加工工艺对钛合金材料进行加工时,存在因低频冲击造成的工件残余应力分布不均匀和表面硬度低等问题,为此,开展了钛合金材料超声振动滚压工艺仿真及实验研究。首先,从理论层面分析了超声滚压加工的运动学及动力学特性,找出了影响超声滚压加工性能的相关因素;然后,采用ABAQUS有限元软件建立了钛合金材料的仿真模型,分析了超声滚压对残余应力的影响及强化机理;最后,设计了钛合金工件的超声滚压实验,研究了不同参数指标对工件加工质量的影响,并根据实验结果对仿真模型和残余应力结果进行了验证。研究结果表明:随着静载荷和超声振幅的增加,工件表面残余应力分布相对均匀且趋于平稳,表面粗糙度呈现先降低后增加的趋势,表面硬度随强化层深度的增加逐渐降低;在振幅为20μm时,工件表面质量和性能相对较好,此时残余应力均值为849 MPa,表面粗糙度均值为0.1μm。该实验结果与仿真分析结果一致,验证了所建模型的可靠性,可为滚压制造工艺参数的选取提供参考。

Aiming at the problem of uneven distribution of residual stress and poor surface hardness in workpieces caused by low-frequency impact in ordinary rolling processing,simulation and tests research on ultrasonic vibration rolling technology of titanium alloy materials were carried out.Firstly,the kinematic and dynamic characteristics of ultrasonic rolling machining were analyzed from a theoretical perspective,and the relevant factors affecting the performance of ultrasonic rolling machining were identified.Then,the simulation model of titanium alloy material was established using ABAQUS finite element software,and the influence of ultrasonic rolling on residual stress and strengthening mechanism were analyzed.Finally,ultrasonic rolling tests were designed for titanium alloy workpieces to study the effects of different parameter indicators on the machining quality of the workpieces.The simulation model and residual stress results were validated based on the tests results.The research results indicate that with the increase of static load and ultrasonic amplitude,the residual stress distribution on the surface of the workpiece is relatively uniform and tends to be stable.The surface roughness shows a first decreasing and then increasing trend,and the surface hardness gradually decreases with the increase of the strengthening layer depth.When the amplitude is 20μm,the surface quality and performance of the workpiece are relatively preferable.At this time,the average residual stress is 849 MPa,and the average surface roughness is 0.1μm.The tests results are consistent with the simulation analysis trend,verifying the reliability of the established model and providing data reference for the selection of rolling manufacturing process parameters.