复合材料的切削加工表面质量

从已加工表面几何特性，加工硬化和残余应力几方面探讨了复合材料的切削加工表面质量问题。研究结果表明，复合材料的已加工表面包含大量的加工所致缺陷，增强体的特性和取向分布，刀具条件是决定复合材料已加工表面形貌的主要因素；复合材料已加工表面硬度甚至低于加工材料，而皮下层材料通常发生显著的加工硬化；微观上复合材料切削变形区的应力状态很复杂，实践上，复合材料的已加工表面常残余压应力，或表面加工缺陷使大部分热应力和弹性恢复应力均被释放。     

切削加工表面质量仿真系统

介绍一种基于 f、n和刀具参数对切削加工影响的仿真系统 ,阐述影响表面质量的原因以及仿真系统设计的思路 ,提出仿真系统对数控加工的意义。     

影响金属切削加工表面质量的因素

随着经济迅速的发展,金属切削加工技术越来越受到人们的关注与重视,同时对我们的生产和生活也造成了巨大的影响。本文主要对金属切削加工中能够控制表面质量的主要因素进行探究,得到控制表面质量的方法,改善控制表面质量的技术方法。从而提高工件的加工效率,生产优质的产品以及能够获取最大的经济效益。     

轴承圈加热切削加工表面质量研究

针对轴承圈易出现疲劳破坏的问题,提出采用预加热硬态切削加工轴承圈外表面的方法。普通硬态切削和预加热硬态切削试验结果表明,将工件内圈预先加热到160℃进行硬态切削加工,有助于减小加工表面的粗糙度,由于内圈加热减小了轴承圈内外表面的温度差,故加工后的表面残余应力显著减小,其值可达-50MPa,加工得到的表面纹理清晰,形貌光滑、规整,刀具进给运动轨迹清晰;加热切削得到的是均匀的锯齿形切屑,并且切屑形态呈螺旋状,与普通硬态切削相比,加热切削过程较为平稳,说明加热切削可获得良好的表面完整性,且不会引来额外的加工硬化。     

导电加热切削地加工表面质量的影响

为在导电加热切削中获得最佳加工表面质量,对加热电流与切削用量的关系进行了试验研究,并对最佳加热电流的概念进行了分析讨论。     

导电加热切削对加工表面质量的影响

为在导电加热切削中获得最佳加工表面质量,对加热电流与切削用量的关系进行了试验研究,并对最佳加热电流的概念进行了分析讨论。     

铝合金车轮镜面加工技术开发及应用

铝合金车轮具有大直径、轻量化、易散热、端经跳动精度高、动平衡量小等优点。铝合金车轮的镜面加工能力对硬件设备和加工工艺要求很高。因此,在车轮的生产过程中采用镜面加工工艺的少之又少。现在使用的一般精车设备无论是软件还是硬件均不满足镜面加工的条件。     

高硅铝合金的切削加工

一、硅铝合金概况铝合金由于具有比重小、强度高等特性，在工业产品中应用非常广泛。在铸造铝合金中，硅铝合金很重要。工业上很重要的硅铝合金可分为三类：1．亚共晶硅铝合金其中含有9～12％的睦。2．共晶硅铝合金含11～13％的硅。3．过共晶硅铝合金硅含量在12％以上，主要是在15～30％范围。共晶成分铸造硅铝合金，由于具有一系列优点，加比重小、线收缩不显著，流动性、抗裂性、耐腐蚀性好等，特别是通过加纳（或钠盐）处理使共晶体变质后，机械性能大有改善，所以在工业上巳得到广泛应用。但是，由于在使用性能方面还存在一些缺点：和耐…     

金刚石刀具研磨质量的影响因素

金刚石刀具研磨非常困难,影响研磨质量的因素较多。     

超精密车削表面粗糙度的控制与优化

金刚石车削是利用高精度机床与锋利的单晶金刚石刀具加工出尺寸精度高、表面完整性好的零件的一种金属加工技术。用回归分析的方法，根据金刚石车削铝合金的实验结果可以建立表面粗糙度预测模型，这种方法能够以较少的实验次数获得大量的加工信息。在一定条件下，利用优化设计软件可以实现切削参数的优选，用优选得到的最优切削参数组合进行超精密加工，能够获得超光滑加工表面。     

薄壁铝合金件的高速切削工艺研究

分析了薄壁铝合金零件的结构特点及加工工艺方案；研究了高速切削中减小其加工变形的切削参数优化策略。采用该措施可以有效地减小薄壁零件的加工变形，保证加工质量；明显地提高生产效率，缩短飞机的制造周期。     

铝锂合金切削加工性的研究

从刀具耐用度、零件表面加工粗糙度和切屑形态３ 个标志方面,对铝锂（Ａｌ Ｌｉ） 合金和超硬铝合金（ＬＣ４） 的切削加工性进行了对比试验。结果表明,Ａｌ Ｌｉ 合金与ＬＣ４ 合金无明显差别,均属易切削和较易切削的材料。这主要因为它们同属可用热处理强化的铝合金,经固溶处理和时效强化后,其组织都是由固溶体和强化相两个基本相组成,因而有着较为相近的机械性能所致。     

超精密车削切屑形成过程的试验研究

超精密车削中的各种物理现象，如切削力、刀具磨损以及加工表面质量等问题，都是以切屑形成为基础的。而生产实践中出现的许多问题，如振动、卷屑和断屑等，又都与超精密切削过程密切相关。选用的材料种类和切削条件不同，可生成不同形态的切屑。文章提出了一种研究切屑形成过程新的试验方法，利用该方法能够得到金刚石车削时高清晰的金属材料塑性流动图像。     

Prediction of the Effect of Tool Interference on Surface Generation in Single-Point Diamond Turning

Tool interference has its origin from the small amplitude and low frequency vibration existing between the tool and the workpiece in single-point diamond turning (SPDT). It inevitably affects the surface quality of a diamond turned surface. In this paper, a surface topography simulation model is proposed for the prediction of the effect of tool interference on surface generation in SPDT. It makes use of the surface roughness profiles predicted at a finite number of equally spaced radial sections of a workpiece to construct the surface topography of a diamond turned surface. The approach overcomes the limitation of the existing theories that can check only for the existence of tool interference. The model was evaluated through practical cutting experiments. Experimental results were found to agree well with the predicted results.     

单晶铝微尺度铣削表面质量实验研究

为探究单晶铝微尺度铣削的表面质量,采用直径为0.4mm的微铣刀对单晶铝进行三因素五水平的微尺度铣削正交实验。首先,通过极差分析的方法得到:主轴转速对其表面质量的影响最大,进给速度的影响次之,铣削深度的影响最小;得到的最优工艺参数组合为:主轴转速为36000r/min,铣削深度为10μm,进给速度为80μm/s,此时单晶铝的表面质量最好。然后,分别得到主轴转速、铣削深度和进给速度对表面质量的影响规律,并对其原因进行了深入分析,为单晶铝材料的微尺度铣削加工提供理论依据。     

Characterization of Tool Wear Measurement with Relation to the Surface Roughness in Turning

In turning, an accurate gauging of tool wear condition is an essential part of process control due to adverse effects on dimensional tolerance and surface finish quality. When the surface roughness is the primary concern, the conventional measure of tool wear is found to be imprecise because it provides very little information on the wear patterns in tool nose and flank. A tool wear model, developed in this study, represents the wear condition more comprehensively and accurately with relation to the surface roughness. Experimental results validate the model, showing 92% accuracy between the predicted surface roughness and the actual measurements.     

Characterization of Tool Wear Measurement with Relation to the Surface Roughness in Turning

Abstract

In turning, an accurate gauging of tool wear condition is an essential part of process control due to adverse effects on dimensional tolerance and surface finish quality. When the surface roughness is the primary concern, the conventional measure of tool wear is found to be imprecise because it provides very little information on the wear patterns in tool nose and flank. A tool wear model, developed in this study, represents the wear condition more comprehensively and accurately with relation to the surface roughness. Experimental results validate the model, showing 92% accuracy between the predicted surface roughness and the actual measurements.     

Tribological Behavior of Aluminum Alloys Implanted with Nitrogen,Titanium Then Acetylene

The composition depth profiles, structure and ball-on-disk frictional characteristics of aluminum alloys 2024 plasma-based ion implanted with nitrogen, titanium and nitrogen then acetylene were investigated. The layers implanted with nitrogen then with nitrogen and titanium and finally with acetylene included three zones: a top DLC (diamond-like carbon) zone, a C, Ti and N coexisting intermediate zone which undergoes chemical changes forming TiC, Ti(C,N), TiN, (Ti, Al)N and AlN second phases, and the bottom zone of the substrate. The micro-hardness and nano-hardness of these layers are HK7.8 GPa and 22 GPa, respectively. The layers showed lower friction coefficient and higher wear resistance. The Raman spectra for worn tracks after sliding for different numbers of cycles showed that when the loading was 1 N after sliding 10,000 cycles, a slight graphitization phenomenon of the DLC film is found. If the loading was 20 N, the graphitization phenomenon of the DLC film is more obvious after sliding 2000 cycles. The SEM morphologies of the wear tracks showed that when the load was 1 N, after sliding 7200 cycles the wear is from rubbing and abrasive wear. When the load was 20 N, after sliding 2000 cycles, delamination wear is dominant.