界面物理性能驱动的钛合金超声磨削关键技术研究

This proposal investigates the scientific problems of ultrasonic assisted grinding of titanium alloy by considering the interface physical performance. It is of great importance not only in the manufacturing theory of titanium alloy, but also in the manufacturing science of geometry and performance for the titanium alloy parts.The main focuses of this project are listed as follows. (1) Develop theoretical, numerical and empirical ultrasonic assisted grinding force models for titanium alloy; (2) Study the thermal-mechanical coupling mechanism and build the related models; (3) Predict and control the ultrasonic assisted grinding induced residual stress for titanium. The Specialty and novelty of this project is listed as follows: (1) Present a comprehensive residual stress modeling method for the ultrasonic assisted grinding of titanium and develop a controllable active manufacturing method by considering the interface physical properties; (2) Find out the approaches to build the thermal source and temperature distribution models and develop the thermal-mechanical model by considering the multiple energy sources. The implement of this project could not only provide technical and theoretical supports for the anti-fatigue manufacturing of titanium alloy parts, but also enhance the surface integrity and fatigue performance of titanium alloy.

项目研究基于界面物理性驱动的钛合金超声磨削相关科学问题，对完善和发展钛合金制造理论、实现钛合金零件成形成性制造具有重要意义。项目重点研究内容有：（1）钛合金超声振动辅助磨削的磨削力建模;（2）超声磨削钛合金的热力耦合机理和定量建模解析; （3）钛合金超声磨削表面层残余应力分布预测控制。项目主要特色和创新包括：（1） 提出面向超声振动辅助磨削加工钛合金表面层残余应力综合建模方法，建立基于表面物理性能驱动的钛合金可控精度主动加工方法；（2）提出超声振动辅助磨削加工钛合金表面超声热源模型、温度场分布的建模方法，建立多能场耦合区域的热力耦合模型；项目研究为钛合金零件的抗疲劳制造提供技术和理论支持，对提高钛合金零件的表面质量和疲劳性能具有一定的作用。

项目从单颗磨粒超声磨削耕犁和切屑成形区域的磨削力微观机理出发，建立了一种砂轮超声磨削力计算预测模型。基于热传导理论，运用逆热传导方法研究并建立基于非高斯型分布的热源模型。并利用热电偶测量得到了磨削区域温度曲线，验证了非高斯分布热源在仿真计算超声磨削温度场时的准确性。基于磨削过程中应力应变场热弹塑性本构关系，加载运动学硬化函数，耦合磨削热及磨削力对超声磨削残余应力场进行有限元数值计算，得到超声磨削表层残余应力分布。设计开发了两套超声磨削系统，系统的研究了超声振幅、频率、砂轮速度、磨削深度、工件进给速度和磨削力、表面粗糙度、残余应力等之间的关联规律。同时，基于随机过程理论，提出了一种三维粗糙表面/砂轮表面表征建模的新方法，大大提高了大尺度砂轮表面建模效率。基于砂轮表面微观形貌模型，建立了考虑耕犁效应的超声磨削表面微观形貌预测模型。项目研究不仅为高强度合金的高效精密加工提供了一种有效途径，也为关键基础件的抗疲劳制造提供了一定的理论指导和技术支撑。