CVD金刚石薄膜刀具加工SiC_p/Al复合材料时的切削磨损研究

通过用CVD金刚石薄膜涂层刀具切削加工SiC颗粒增强铝基复合材料的试验 ,研究了切削参数、刀具材料、刀具几何参数和工件材料对CVD金刚石薄膜涂层刀具磨损的影响规律 ,同时研究了SiCp/Al复合材料的切削加工性能。     

CVD金刚石薄膜刀具加工SiCp／Al复合材料的切削磨损研究

通过用CVD金刚石薄膜涂层刀具切削加工SiC颗粒增强基复合材料的试验,研究了切削参数、刀具材料、刀具几何参数和工件材料对CVD金刚石薄膜涂层刀具磨损的影响规律,同时研究SiCp/Al复合材料的切削加工性能。     

晶粒细化对金刚石涂层刀具切削性能的影响

金刚石涂层具有高硬度、低摩擦系数、高耐磨性和高导热性能。本文着重介绍了金刚石涂层刀具的发展动向及现状,并通过金刚石涂层刀具的切削试验表明了金刚石涂层刀具的使用寿命明显高于未涂层的硬质合金刀具,采用金刚石涂层刀具进行切削可以获得更高的表面加工质量和生产率。     

金刚石涂层刀具在干式切削中的性能分析

介绍了干式切削加工技术的优点及发展趋势,分析了干式切削刀具技术及金刚石涂层刀具的性能特点.通过铝硅合金的干式切削试验,研究了金刚石涂层刀具的干式切削加工特性.经试验表明,金刚石涂层刀具正常磨损阶段,工件表面粗糙度非常稳定;刀具损坏以涂层脱落为主,刀具寿命取决于涂层与机体的结合强度;进给量对工件表面粗糙度影响最大,如果进给量合适,可以保证金刚石涂层刀具在高速下具有良好的干式切削性能.     

TiAlN涂层刀具对不同调质状态40Cr钢切削性能研究

为了更好地指导TiAlN涂层刀具在金属切削加工中的应用,采用物理气相沉积法制备了TiAlN涂层刀具,应用TiAlN涂层刀具和未涂层刀具对不同调质状态的40Cr钢进行了干式切削试验。通过对切削过程中切削力和切削温度检测,考察了TiAlN涂层刀具的切削性能。结果表明,与YTl5硬质合金刀具相比,TiAlN涂层刀具适合切削高硬度的金属材料,且优越性更明显。     

氮化碳涂层刀具干切削性能的研究

采用dc反应磁控溅射法在硬质合金 (YT15 )上沉积氮化碳超硬涂层 ,将其应用于干切削领域 ,通过对硅铝合金和淬火钢的干式切削试验 ,研究了氮化碳涂层刀具的切削加工性能。切削试验表明 ,在干式切削加工硅铝合金时可以达到较高的表面粗糙度 ,完全能满足生产要求 ;在淬火钢加工中 ,与未涂层的刀具相比 ,刀具寿命有较大提高     

氮化碳涂层刀具干式切削研究

通过与传统湿式切削加工的对比,介绍了金属干式切削加工的技术优点和发展趋势,分析了氮化碳涂层刀具的特点。通过干式切削淬火钢的试验,分析了涂层刀具干式切削加工的技术特点及刀具的磨损机理。试验表明,氮化碳涂层能够很好地保证干式切削的进行,涂层一旦磨损,刀具很快磨损;切削参数中切削速度对刀具寿命影响最大。     

高速切削加工刀具材料的运用分析

高速切削加工是机械制造业发展的必然趋势,高速切削刀具材料的应用对切削技术具有决定性的作用,涂层刀具、超硬材料、陶瓷刀具等得到了广泛的应用,高速切削刀具系统日趋完善,成为推动高速切削加工的重要组成部分。     

陶瓷涂层硬质合金刀具的性能

本文详细介绍了Al_2O_3涂层刀具的优越性能及其与TiC涂层刀具、普通陶瓷刀具和硬质合金刀具加工各种材料的性能比较试验结果。文章还对涂层厚度和合理切削条件作了研究。     

热喷涂涂层机械加工技术及应用

结合热喷涂涂层的性能和特点,分析了热喷涂涂层的主要切削加工性以及影响涂层切削加工的因素,并通过加工方法、切削刀具以及工艺参数选择的加工应用实例,解决热喷涂涂层的机械加工问题。     

刀具涂层材料的发展

采用涂层技术可有效提高切削刀具的使用寿命,使刀具获得优良的综合机械性能,从而大幅度提高机械加工效率.我国的刀具涂层材料经过多年发展,目前正处于关键时期,充分了解国内外刀具涂层材料的现状及发展趋势,有计划、按步骤地发展刀具涂层材料,对提高我国切削刀具制造水平具有重要意义.     

Enhancing the machining performance by cutting tool surface modifications: a focused review

In machining, cutting tools suffer from severe surface wear, especially in the cutting of difficult-to-cut materials. A major cause of tool wear is the friction generated at the tool-work and tool-chip interfaces, which produces a great deal of frictional heat and abrasion. In order to extend tool life and improve the quality of machined components, a host of techniques have been applied to modify the rake and flank faces of cutting tools. These techniques aim at providing cutting tools with improved resistance to external loading, better tribological performance and/or better chemical stability. This article presents a review of the fundamentals behind which the friction and wear in machining are reduced by modifying the cutting tool surface with the commonly used techniques, such as surface coating, high energy beam treatment, and surface texturing. The effects of these surface modifications on improving the cutting performance are also analyzed. Future research directions are finally discussed.     

涂层硬质合金刀具干式切削淬硬钢的试验研究

通过采用涂层硬质合金刀具对淬硬 4 5钢硬态干式切削试验 ,分析硬态干式切削淬硬钢的特点 ,研究了涂层硬质合金刀具及其几何参数的优化 ,讨论了涂层硬质合金刀具磨损形式、刀具耐用度及加工表面粗糙度 ,得出了可应用于实际干式切削加工的切削条件和参数     

Performance of cutting tools with dimple textured surfaces: A comparative study of different texture patterns

Recently, surface texturing has received much attention as a method of enhancing the tribological properties of a cutting tool surface. However, effective texture patterns and dimensions on a tool surface are still difficult to obtain and suitable textures can be obtained only by trial and error. In order to overcome this problem, we newly develop cutting tools with dimple-shaped textures having different dimensions and arrays, generated on the tool rake face. In addition, we evaluate their crater wear resistance and cutting forces in steel material cutting. Furthermore, under various cutting conditions, the performances of the cutting tools with dimple-shaped textures are compared with those of tools with groove-shaped textures in order to establish a guideline for designing appropriate surface textures on cutting tool surfaces. A series of cutting experiments demonstrate that the dimple textures significantly improve the crater wear resistance and the tribological behavior on the tool rake face, and they exhibit a superior performance compared with those with groove textures, especially in a severely lubricated environment.     

Damage of physical vapor deposition coatings of cutting tools during alloy 718 turning

Ni-based superalloys are typically difficult-to-cut materials. Therefore, the lifespan of cutting tools used to cut these materials is shorter than that of tools used on other materials. This study develops a new coating for cutting tools that has properties required for the turning of Ni-based superalloys. This study examined the cutting performance of TiN-coated cutting tools deposited by arc ion plating according to the damage of the coating and determination of the required properties of the coatings. To evaluate cutting tool damage, many analysis methods were used at each step of damage accumulation. Plastic deformation of the coating was observed at rake and flank face edges by scanning ion microscopy and transmission electron microscopy (TEM). Furthermore, the fracture of the coating near the surface defects (e.g., droplets, voids) was due to the interaction between the work material and surface defects. Moreover, using electron probe microanalysis, scanning auger microscopy, and TEM, the work material was confirmed to adhere to the cutting edge physically or mechanically, not chemically. This means that oxidation and diffusion did not occur in the interface between the adhesive material and coating after cutting. Finally, the effectiveness of different coating types, varying in both composition and deposition method, was verified by evaluating the effect of damage reduction. Using coatings with greater stability at high temperatures and fewer defects can reduce damage of the coated cutting tools, increasing tool lifespan.     

绿色切削加工技术分析

21世纪的制造业实施绿色制造已势在必行，绿色切削加工技术的研究应运而生。干切削技术避免了切削液的副作用，但它对刀具提出更高的要求；切削液最少量润滑技术能够使切削工作处在最佳状态下，切削液的使用量达到最少，但绿色切削液需深入研究。笔者认为，实现绿色切削加工的关键技术是：1）开发刀具技术。包括新型刀具材料和刀具涂层技术的研究和应用，优化刀具形状及结构；2）开发绿色切削液技术，包括切削液的绿色设计与绿色使用，开发切实可行的废液处理新工艺。     

Machining of austenitic stainless steels using CVD multi-layer coated cemented carbide tools

This paper presents the results of experimental work in dry turning of austenitic stainless steels (AISI 304 and AISI 316) using CVD multi-layer coated cemented carbide tools. The turning tests were conducted at four different cutting speeds (120, 150, 180 and 210 m/min) while feed rate and depth of cut were kept constant at 0.16 mm/rev and 1 mm, respectively. The cutting tools used were TiC/TiCN/TiN and TiCN/TiC/Al₂O₃ coated cementide carbides. The influences of cutting speed, cutting tool coating top layer and workpiece material were investigated on the machined surface roughness and the cutting forces. The worn parts of the cutting tools were also examined under scanning electron microscope (SEM). The results showed that cutting speed significantly affected the machined surface roughness values. With increasing cutting speed, the surface roughness values decreased until a minimum value is reached beyond which they increased.     

刀具涂层技术及涂层刀具切削性能的试验研究

在阐述刀具硬质涂层技术发展新动向的基础上,通过车削、铣削及攻丝的切削试验证明:涂层刀具的切削力总比未涂层刀具的小,且不同涂层刀具的切削力减小程度不同,在试验的几种涂层刀具中,AlTiN涂层、TiCN-WS2涂层刀具的切削力减小得多些.     

Elliptical vibration cutting of hardened die steel with coated carbide tools

Elliptical vibration cutting of hardened die steel with coated carbide tools is examined in this research in order to achieve low-cost high-precision machining. Diamond coated tools are applied because of superior hardness of their polycrystalline diamond coating and its low manufacturing cost. TiN coated tools are also tested, since they are widely used for conventional machining of steels. Machinability of hardened die steel by the elliptical vibration cutting with coated carbide tools is discussed in three aspects in this study, i.e. transferability of cutting edge profile to cut surface, cutting force, and tool life. The transferability is evaluated quantitatively by calculating correlation coefficients of measured roughness profiles. It is clarified that the diamond coated tools have high transferability which leads to diffraction of light on the surface machined at micro-scale pick feed. Total cutting forces including ploughing components are measured at various feed rates, and then shearing components and ploughing components are separated utilizing linear regression. The measured results indicate, for example, that the all forces become considerably smaller only when elliptical vibration is applied to the TiN coated tool without cutting fluid. It is also found that this considerable reduction of forces interestingly corresponds to higher friction coefficient, which is identified from the ploughing components. Tool life tests are carried out by various machining methods, i.e. elliptical vibration/ordinary wet/dry cutting with diamond/TiN coated tools. The result shows, for example, that the flank wear is smallest in the wet elliptical vibration cutting with the diamond coated tool.     

EFFECT OF COATING ROUGHNESS ON PERFORMANCE OF SMALL CVD DIAMOND COATED TOOLS

□ Small milling tools for dental application were diamond coated by means of Hot Filament CVD (HFCVD). Different thicknesses were obtained by using different diamond deposition times (3 and 12 h) and seeding conditions. The surface roughness was measured for coated and uncoated mills and milling tests were performed to measure the cutting forces. A ceramic material and a polymeric matrix composite (PMC) were used as workpiece materials. The highest cutting forces were measured for the coated tool with the highest thickness of the diamond coating. Probably, roughness increase and non-optimal edge profiles affect the tool behavior during cutting. As a consequence, tool failure was observed in the case of milling of ceramic by means of the coated tool with the highest coating thickness. The coated tool with a lower thickness of the diamond coating showed an optimal behavior under cutting, above all in the case of PMC milling.