基于“固-隙-固”接触模型的结合面振动-摩擦耦合机理与动力学特性研究

This project takes the research object of linear-feed-system movable joint surfaces, makes the theoretical basis on fractal contact theory, nonlinear vibration and tribology, and completes the research of joint surface vibration-friction coupling mechanism, dynamic characteristics analysis and dynamic characteristics change law from microcosmic to macroscopic perspective: it establishes "rigid-clearance-rigid" contact model of joint surfaces, studies how to express the surface treatment characteristics and material characteristics of interface, determines the component interface area and generalized clearance scale of joint surfaces, and finally reveals force distribution and force transfer law; by combination of theoretical analysis and experiment, it studies vibration law of the vibration and impact generated by cutting force, fluctuation of feeding force or feeding speed, and reciprocating motion or stick-slip movement of platform, thus, vibration evolution law along with the surface treatment characteristics and material characteristic parameters of joint surfaces can be explored; according to different vibration sources, this item studies influence law of friction caused by vibration frequency, amplitude, direction and phase; besides, it also studies dynamic characteristic analysis of joint surfaces in different motion state and change law of dynamic characteristics along with the surface treatment characteristics, material characteristic and external excitation; so that some effective ways and methods of adjusting and controling the dynamic characteristics of joint surfaces can be explored. By researching, the theoretical basis for design selection, production and error compensation can be provided, meanwhile, the technical support of predicting and controling dynamic performance can also be offered.

项目以直线进给系统导轨运动结合面为研究对象，以分形接触理论、非线性振动和摩擦学为理论基础，先微观后宏观，完成了结合面振动-摩擦耦合机理、动力学特性分析和动力学特性变化规律的研究：建立结合面"固-隙-固"接触模型，研究如何表征接触面表面处理特征和材料特性，确定结合面的构件界面区域和广义间隙的尺度，揭示力场分布和力传递规律；通过理论分析与实验相结合，研究切削力产生的振动与冲击、进给力和进给速度的波动、运动平台的往复运动、粘滑运动的振动规律，探索振动规律随结合面表面处理特征和材料特性参数的演化规律；针对不同振动源，研究振动频率、幅值、方向和相位对摩擦力的影响规律；研究不同运动状态下结合面的动力学特性分析和动力学特性随表面处理特征、材料特性和外部激励变化的规律；进而探索调整和控制结合面动态特性的有效途径和方法。通过研究为设计选材、制造和误差补偿提供理论依据，也为预测和控制动态性能提供技术支持。

根据项目的计划书，围绕预定的研究内容进行了具体研究，基本实现了项目预期目标，并取得了一定成果。. 项目完成了以下四个方面的内容：结合面的“固-隙-固”模型构建及广义间隙参数辨识；基于“固-隙-固”模型的结合面接触理论建模；结合面的振动-摩擦耦合作用特性分析；单轴直线系统不同工况下的动态变化规律研究。通过研究建立了结合面间的“固-隙-固”接触模型；确定了结合面的构件界面区域、广义间隙尺度；辨识了结合面间广义间隙的等效参数；完成了粗糙平面间、曲面间接触的法向和切向接触刚度、阻尼分形模型，分形模型的给出可为后续的整机动力学建模提供基础；建立了典型自激振动模型、制动模型和单轴直线运动模型，分析了结合面参数对模型的非线性动力学影响；探索表面处理和材料参数表征对振动规律的演化；试验研究了结合面非线性特性对制动系统及单轴直线运动系统的影响规律。. 通过项目研究，获得的成果有：发表学术论文22篇，其中SCI检索3篇，EI及CPCI（ISTP）检索19篇次；培养在读博士研究生3名，硕士研究生14名；申请发明专利2项。