超声波加工参数的实验研究

超声波加工己被证明是陶瓷、金刚石、半导体等硬脆性材料加工的有效方法,但其加工效率不高制约着它的广泛应用。因此根据超声波加工材料去除率模型,对磨料粒度、静载荷等加工参数进行探讨,可得出各加工参数对材料去除率的影响。     

金刚石工具头超声波复合加工的实验研究

研究了金刚石工具头超声波复合加工方法的可行性及加工参数与材料去除率的关系。在研究超声加工，超声复合加工和金刚石工具的基础上，借助SEM分析其典型塑性材料和脆性材料的加工形貌，初步讨论了该方法去除材料的机理。     

HAP/SiCw复合生物陶瓷材料的超声波加工

研究了用超声波加工技术对HAP/SiC复合生物陶瓷材料进行加工时晶须取向对加工机理、材料去除率和加工表面粗糙度的影响。研究结果表明材料去除率和加工表面粗糙度随晶须方向角的增大而增大。在相同的加工条件下 ,材料的断裂韧性越高 ,其MMR越小。该研究为HAP/SiCw复合生物陶瓷材料的超声波加工提供了工艺依据     

超声振动钻削加工陶瓷的研究 Ⅱ实验研究分析

本刊上期刊登的第一篇基本原理分析，从理论上分析了采用超声振动钻削时的材料去除机理，建立了材料去除率模型，推导了材料去除率公式。为了在实际生产中有效地应用超声振动钻削加工方法，本篇就所进行的实验研究，探讨了超声振动钻削中各项工艺参数对其加工效果的影响，记述了实验研究的情况。     

超声波加工建筑玻璃小孔的试验研究

本文通过超声波加工建筑玻璃小孔的试验，探讨了工具振动的振幅、频率、工件材料、进给压力、工作介质等主要加工参数对去除率和影响和工具设计及加工效果。     

大理石的超声波加工试验研究

本文采用超声波加工技术对大理石的孔加工进行了试验研究,并与陶瓷材料进行了对比试验,研究了各种加工参数对材料材料率和加工精度的影响。试验结果表明：材料去除率与其力学性能有关,在同样的加工条件下,材料的强度和断裂韧性越高,其材料材料率越低,加工精度越高。     

光学玻璃的超声铣削研究

介绍了光学玻璃的超声波铣削加工.重点分析了光学玻璃常见的加工方法,并进行了比较.根据光学玻璃精密加工的特点,详细介绍了超声波铣削加工的优点及可行性.研究表明,采用超声波铣削能提高加工效率,加工过程便于检测控制.使用超声波铣削加工可以提高光学玻璃的加工精度,节约加工成本,改变了光学玻璃加工费时费财的现象.对光学仪器或机械...     

超声波加工建筑玻璃小孔的试验研究

本文通过超声波加工建筑玻璃小孔的试验，探讨了工具振动的振幅、频率、工件材料、进给压力、工作介质等主要加工参数对去除率的影响和工具设计及加工效果。     

线电极放电铣削凹坑的材料去除率规律研究

线电极放电铣削加工是一种新型电火花铣削技术，它的最大优点是可通过线电极的缓慢移动来补偿加工中的电极损耗。在其加工过程中，由于较多的参数影响（包括电参数和非电参数）及复杂的放电机理，要获得理想的加工效果相当困难。为此，本文通过试验对线电极放电铣削材料去除率进行了初步研究。     

超声波磁流变复合抛光中几种 工艺参数对材料去除率的影响

提出了一种光学抛光的新方法——超声波磁流变复合抛光。介绍了该抛光方法的基本原理和实验装置,进行了超声波磁流变复合抛光实验,采用轮廓仪实测了光学玻璃超声波磁流变抛光材料去除轮廓曲线。通过该项工艺实验,研究了五种工艺参数(磁场强度、超声振幅、抛光工具头与工件的间隙、抛光工具头转速、工件转速)对光学玻璃材料去除率的影响。在一定实验条件下,获得的材料去除率为0.139 μm/min,并获得了超声波磁流变复合抛光工艺参数与材料去除率的关系曲线,得出了光学玻璃超声波磁流变复合抛光的材料去除规律。     

Mathematical model for cutting force in rotary ultrasonic face milling of brittle materials

Rotary ultrasonic machining of brittle materials, such as glass, ceramics, silicon, and sapphire, has been explored in a large number of experimental and theoretical investigations. Mechanistic models have been developed to predict the material removal rate or cutting force in the rotary ultrasonic machining of brittle materials. However, most merely describe the rotary ultrasonic machining process of drilling holes in brittle materials. There are no reports on the development of a cutting force model for flat surface rotary ultrasonic machining, i.e., rotary ultrasonic face milling. This paper presents a mathematical model for the cutting force in the rotary ultrasonic face milling of brittle materials under the assumption that brittle fracture removal is the primary mode of material removal. Verification experiments are conducted for the developed cutting force model and show that the trends of input variables for the cutting force agree well with the trends of the developed cutting force model. The developed cutting force model can be applied to evaluate the cutting force in the rotary ultrasonic face milling of brittle materials.     

An analytical model of rotary ultrasonic milling

Rotary ultrasonic machining is currently being used as a manufacturing method for advanced ceramic materials, but its complexity has hindered its acceptance in industry. For this technology to gain wider acceptance, it must first be scientifically better understood. The majority of published rotary ultrasonic machining (RUM) papers studied the effect of RUM process parameters on machining performance and removal mechanisms for drilling of circular holes. In industries such as aerospace, the production of advanced turbine components requires machining of complex 3D features using milling strategies. The objective of this paper will be to present a new physical model based on rotary ultrasonic milling which will help provide a better scientific understanding of the process. This will be accomplished by first modeling the macro kinematics between the tool and material followed by the modeling of micro kinematics between the individual diamond grains and the material. In addition, a force model for predicting machining process forces will also be introduced and validated based on a set of experiments. The physical models will help determine the relationships between input parameters, cutting parameters, and process output parameters for rotary ultrasonic milling.     

超声波在机械研磨加工中的应用与研究

为了提高机械研磨的材料去除率,探讨了在机械研磨的界面上引入超声能的复合研磨方式,将机械研磨和引入超声的复合研磨两种方法的去除效率进行了实验对比;发现复合研磨后,去除效率有显著提高;得出超声/机械复合研磨的加工效率明显优于机械研磨。所获得的工艺规律对于工业生产具有一定指导意义。     

Research into the transition of material removal mechanism for C/SiC in rotary ultrasonic face machining

Ceramic matrix composites of type C/SiC with superior properties have got increasing importance in many fields of industry, especially in the aerospace area. Rotary ultrasonic machining is a high-efficiency processing technology for these advanced materials. However, due to the inhomogeneity and anisotropy of these composites, the machining process is still challenging to achieve desired result due to the lack of understanding and control of material removal mechanism. In this paper, the maximum depth of penetration by diamond abrasives in workpiece material is proposed to quantify the material removal modes. A model of maximum depth of penetration for rotary ultrasonic face machining (RUFM) was developed based on the indentation theory. An experimental RUFM of C/SiC was carried out, and it revealed that the material removal mechanism transited from ductile mode to brittle fracture mode with the decrease of cutting speed. Similar transition was observed with the increase of feed rate and cutting depth. By comparing the measured cutting force with simulation, a critical depth of penetration for the cutting mechanism transition was defined at about 4 μm. The processed surface topography was studied, and the transition of material removal modes was identified by the sudden change of the 3D surface roughness map at the critical penetration depth. Thus, the maximum depth of penetration model developed in this paper can be applied to identify the ductile or brittle fracture removal mode in RUFM of C/SiC using the cutting parameters. This allows controlling the material removal mechanism to achieve desired machining efficiency and quality.     

超声纵扭辅助铣削高强铝合金表面润湿性能研究

针对超声辅助加工在工件表面形成微刻划表面可以提高高强铝合金表面的微结构性能的现象,进行了单激励旋转超声纵扭复合铣削表面微观结构的试验,基于水接触角理论和纵扭铣削运动学理论分析了加工参数对水接触角的影响;搭建了单激励超声纵扭铣削试验平台,采用正交试验法研究了不同加工参数对表面粗糙度、铣削力以及表面润湿性能的影响。结果表明：超声振幅为4 μm时表面质量最佳,切削速度和进给量与表面粗糙度和水接触角呈正相关的关系;超声加工方式下的表面水接触角较普通方式更大,而在超声加工时低振幅加工比高振幅加工的表面水接触角大,当转速达到一定值时,高振幅和低振幅所加工的表面水接触角差别不大。合适的加工参数条件下超声纵扭加工方式可以降低加工表面的粗糙度,改变表面的润湿性。     

高温合金蜂窝芯高速铣削材料去除机理与损伤行为

高温合金蜂窝芯材料具有高比刚度、轻质和能量吸收特性好等优异性能,被视为下一代高超声速飞行器热防护结构极具潜力的材料。高速铣削是高温合金蜂窝芯零件成型过程中重要的减材制造工艺,在蜂窝芯材料高速铣削时,蜂窝芯材料面内刚度低且高温合金塑性好,较小的切削力就会使蜂窝壁产生较大的塑性变形,导致蜂窝芯加工精度较低、加工损伤难以控制,对后续焊接、装配等工序产生不利影响。基于有限元仿真对蜂窝壁切削材料去除机理进行了深入研究,探索了铣削参数、刀具类型和铣削方式对铣削过程中铣削力和加工损伤的影响。研究结果表明,蜂窝壁切入角是影响蜂窝芯材料切削加工过程中瞬时应力分布和成屑机理的关键性因素。得到了铣削参数、刀具类型和铣削方式对高温合金蜂窝芯加工过程中加工损伤的影响规律。对于铣削参数,过大的进给量会导致芯格变形等加工损伤,降低切削速度会提高微小毛刺等加工损伤发生的频率;本文采用的三种刀具的对比结果表明,立式铣刀加工质量最好。插铣方式会产生明显的轴向冲击,而侧铣方式可以有效避免轴向冲击。研究成果为高温合金蜂窝芯低损伤高性能加工提供了理论依据和工艺技术储备。