航空叶片制造工艺及坐标检测方法分析

以当前航空发动机制造现状为研究对象,简要概述电解加工、数控加工、精密锻造及超塑性成形等叶片主流加工工艺及其制造关键性技术,并引出发动机叶片制造过程的测量手段。阐述三坐标测量过程中叶片坐标定位、测量轨迹规划及点云降噪的实现方法;简要分析了激光测头安装精度、激光投射角度、测量景深等对激光扫描法测量精度的影响。对航空叶片精密制造工艺及与之相适应的高效精密检测技术快速发展具有一定指导意义

Research on the Technology and Experiments of Two-dimensional Ultrasonic Vibration Assisted Fixed Abrasive Machining

化学机械抛光（CMP）加工应用广泛，由于游离磨粒的加工特点，使得加工中材料去除量极其微小，可以获得很好的表面粗糙度。但与固结磨粒加工方式相比，CMP工艺可控性较差，同时基于压力的加工控制，对于工件的面形几何精度相对较难保证。在CMP基础上发展而来的化学机械磨削（CMG），兼有CMP和固着磨粒加工的特点，是获得高加工质量的新方法。而在超精密加工领域，超声波辅助加工及其机理研究正在兴起，主要应用在降低磨削力、提高硬脆材料延性域磨削及加工效率方面，以获得更高面形精度和较小加工损伤。因此，以保证加工精度、提高加工效率为目标，本文将二维超声振动辅助加工技术引入CMG，进行二维超声振动辅助CMG技术开发及...At present, chemical mechanical polishing (CMP) is one of the most important polishing technologies, and fully developed. It is known that CMP can obtain fine surface due to tiny material removal but low machining efficiency, and that the controllability of CMP is quite indeterminate as the typical loose abrasive process. And the chemical mechanical grinding(CMG) process developed based on CMP has...学位：博士后院系专业：物理与机电工程学院机电工程系_机械工程学号：BH170022

磁性抛光对3D打印微结构的参数影响

对微结构精密加工时要能够控制高低不平的材料去除,以保证不破坏微结构原来的三维形貌特征。通过自行搭建的实验平台对3D打印出来的微结构工件进行抛光实验,主要研究了机床主轴转速、加工间隙、抛光时间和抛光路径等工艺参数对微结构抛光后的三维轮廓材料去除特性以及微结构的保形情况。实验结果表明:微结构保形系数随着抛光时间增加而变小,而主轴转速和加工间隙的变化对保形系数影响较小;采用等高线移动式抛光的保形系数比采用水平移动式大;相同工艺参数抛光对包体状和圆环阵列微结构工件保形效果较好,对三棱锥工件保形效果较差。国家自然科学基金(51675453);;深圳市科技计划项目(JCYJ20160517103720819

Study on Remove of Free-Form Surface Structure by Magnetic Polishing

磁性抛光因柔性工具的工件表面适应性高而具有较好的应用潜力。自行设计抛光工具头,制备磁性抛光体,搭建试验平台,并对不锈钢平面工件进行定点抛光试验,平均去除效率为0.231μm/10min,且工件表面质量得到了很大的改善,验证了该磁性抛光方法的可行性。继而对两种自由曲面结构工件进行抛光：一是采用工具头水平移动式、工具头等高线移动式两种不同的抛光进给运动方式对不同曲率的不锈钢工件进行抛光去除试验,试验证明：两种抛光方式对每个曲率的轮廓均有去除能力,去除量在0.14~1.33μm之间;二是对3D打印的光敏树脂微结构自由曲面定点抛光,单位时间去除效率在8.957~12.587μm/10min之间,且改善了轮廓的光滑度。初步试验表明,磁性抛光方法对两种自由曲面结构均有一定的去除能力,可进一步探索磁性抛光技术应用于自由曲面结构确定性抛光。Magnetic polishing technique has wide application potential due to the high adaptability of flexible tool to the workpiece surface. The relevant polishing tools were developed, and a test platform was established in the paper. The workpiece finish had been greatly improved after spot polishing on stainless steel flat parts, and the average removal efficiency was 0.231μm/10 min, which verified the feasibility of the magnetic polishing method. Then two kinds of free-form surface structures were polished by magnetic polishing method. First, stainless steel parts with different curvatures were polished by two different polishing feed movement ways. Experimental results showed that two polishing methods had the ability to remove the contours of each curvature, and the removal amount falls between 0.14-1.33μm. Secondly, the removal efficiency was between 8.957-12.587μm/10 min after spot polishing the microstructured free-form surface, and the smoothness of the contour is improved. Preliminary experiments showed that the magnetic polishing method had the ability to remove both free-form surface structures, so it can explore further magnetic polishing technology used in deterministic polishing of free-form surface structure.深圳科技计划项目（JCYJ20160517103720819

超精密磨床系统振动监控及平衡技术研究

针对高精度磨削加工中磨床系统振动监控及主轴、砂轮平衡的需要,提出基于虚拟仪器设计的振动信号采集及分析系统。该系统由单片机的信号采集单元和上位计算机处理系统组成,具有加工状态实时监控、信号采集存储、信号分析处理、平衡计算、控制输出等功能。试验结果表明:系统的理论分析方法和功能满足设计要求

Surface texture analysis for ultra-precision flycutting machining based on the dynamic characteristics of machine tools

采用超精密飞切加工技术可获得软脆性平面光学元件的最终表面,而元件表面微观形貌的加工可控性对于光学元件使用性能有直接影响。首先运用多尺度小波分解方法,对飞切机床的加工表面波纹进行了特征提取,得到了工件表面波纹的频率组成及占比;然后通过对机床主轴系统的有限元分析,结合冲击振动测试,找到了与工件表面波纹对应的模态;最后通过对机床的在线振动测试及加工实验进一步明确了飞切加工表面微波纹的成因。结果表明:表面波纹在17 mm左右的空间周期上存在最大的分量,显著影响光学元件的精度和使用效果,该波纹由主轴系统在间断切削的冲击响应所引起,可以通过改变主轴结构实现波纹频率和幅值的控制。Ultra-precision flycutting is widely used to machine soft and brittle plane optical elements,and the controllability of micro surface texture affects the performance of the element directly. The multi-scale wavelet decomposition was used to detect the wave feature of the optical element machined by flycutting machine tool,and the frequency and percent of the waves were achieved. The relevant modals of those waves were found by the finite element analysis and the response test of the spindle system. Particularly,online vibration test and machining experiments were conducted to verify the factor bringing about the micro surface texture on the element. The results show that the micro surface texture at a space period of 17 mm is the most prominent and will make worse observably the accuracy and application of the element,which is caused by the response of the spindle system during the machining process. In addition,modifying the structure of spindle system can make a difference on the amplitude and frequency of the wave.国家级基金(2013ZX04006011-102-001

Study on single-plane biaxial balance monitor system in ultra-precision aspheric grinding

提出一个智能型双轴动平衡监控系统,针对高精度加工中工件和工具的振动会相互作用而影响加工效果,该系统同时对砂轮主轴和工件主轴进行平衡,集中处理工具和工件的振动数据,综合分析整个加工系统的平衡效果及工件的表面误差情况,从而达到减少工件加工误差,降低设备磨损,提高磨削加工精度的目的。实验结果表明,对振动数据的分析是正确的,可实现高精度的非球面加工。An intelligent single-plane biaxial balance monitor system in ultra-precision grinding was put forward.For influence of the interaction of vibration of wheel and workpiece on a ripple on the workpiece surface, this system adopts single-plane balance correction for the principal axises of wheel and workpiece synchronouslly,and it analyzes integrally the balance condition of whole system and the surface error of workpiece by processing the vibration data of wheel and worpiece together.The experimental results show that this system can reduce the surface error of workpiece and decrease the abrasion of wheel to improve machining accuracy.The measuring data prove the correction of integral analyses.国家863计划项目(No.8638042416

Study on Measuring Path and High-precision Curve Fitting Algorithm for Axisymmetric Aspheric Optics

为适应轴对称非球面光学元件面形检测的要求,建立了三种不同的检测路径,并对三种路径进行了评价和对比,阐明其优缺点及适用情况,进而建立了一种高精度数据处理系统。采用Gauss-Newton算法进行非线性最小二乘曲线拟合,分别以单调型和超二次型非球面方程为数学模型验证了该曲线拟合算法的精确性。试验结果表明:该算法的拟合误差在1nm数量级,可用于完成高精度的数据曲线拟合。In accordance with the requirements of axisymmetric aspheric measuring,three paths were put forward and estimated.The applicant situations of these three paths were analyzed.A data processing system with high precision was carried out.The Gauss-Newton method was adopted as the curve fitting algorithm for the axisymmetric aspheric surface.The monotonous and super-quadric equations of axisymmetric aspheric lenses were taken as the polynomial mathematics model to verify the accuracy of the nonlinear least square fitting method respectively.The experimental results indicate that the fitting residual errors are in the 1nm magnitude order,so the curve fitting algorithm can be used in the high-precision curve fitting exactly.国家863高技术研究发展计划资助项目(2006AA804206);; 福建省科技重大专项/专题资助项目(2006HZ0002-4

Two Dimensional Ultrasonic Vibration Assisted Chemical Mechanical Grinding and Experiment on Si Wafer

为了提高材料去除率和加工通用性,本文提出了工具施加二维超声波振动辅助的化学机械磨削(CMg)复合加工方式,开发具有伸缩和弯曲两种模态的二维超声波振动子及实验装置.以单晶硅片为加工对象,进行单点切削加工轨迹特性分析,并比较不同加工模式以及加工参数对表面粗糙度和材料去除率的影响.实验结果表明,二维超声辅助下的单点切削轨迹存在更多延性加工趋势.在同样普通机床精度条件下,随着时间的增加,二维超声辅助CMg表面粗糙度明显改善,达到纳米级.较无超声情况下二维超声波辅助CMg复合加工材料去除率提高约1倍,可获得最优表面粗糙度5 nM,一维径向超声辅助加工结果次之.To improve material removal rate and machining popularity,two dimensional ultrasonic vibration assisted chemical mechanical grinding(CMG) was introduced in this paper as the combined grinding method.And two dimensional vibrators with longitudinal and bending modes and integrated experimental installation were developed.Si wafer was taken as machining material,and the experiments were carried out to examine the characteristic of machining locus using single point cutting,and the influence of different machining modes and parameters on surface roughness and material removal rate.The results show that two dimensional ultrasonic assisted single point cutting locus makes more ductile removal.When using the general-purpose machine,two dimensional ultrasonic assisted CMG can obtain better surface roughness at nanometer level as the machining time increases.Compared with conventional CMG without ultrasonic vibration the material removal rate improves by 100% and the best surface roughness is 5 nm.Two dimensional ultrasonic assisted CMG yields the best surface roughness and the largest material removal rate,and one dimensional radial ultrasonic assisted CMG is relatively backward.国家高技术研究发展计划(863计划)资助项目(2008AA042501);国家自然科学基金资助项目(50905150

超精密飞切机床结合面虚拟材料法建模及模态优化

在超精密飞切加工中,机床自身的动态特性是引起加工表面微波纹的主导因素。为探究超精密金刚石飞切机床的动态特性及其对加工表面微波纹的影响机理,将虚拟材料法的结合面建模方法引入整机动力学模型中。进一步地,利用有限元分析软件进行整机的模态分析及优化。结果表明:相较于传统的弹簧-阻尼模型,该模型具有更高的综合精度。同时模态分析表明,机床固有频率为268 Hz的第五阶模态对加工尤为敏感,而通过适当增加结合面的结合刚度,可优化机床模态进而消除波纹提高表面质量。科学挑战计划(JCKY2016212A506-0504