TaC_p增强YG11C合金表面改性工艺及性能研究

选用自制烧结的YG11C/TaC_p硬质合金作基体,介绍了采用电弧离子镀在试样上沉积TiN、TiCN和ZrN涂层的工艺.利用维氏硬度计、扫描电子显微镜、X射线衍射仪表征了涂层的力学性能和组织结构.通过比较切削实验中刀具的磨损性,得出涂层刀具有更好的耐磨性能.研究表明,电弧离子镀TiN等涂层能使硬质合金刀具获得更好的使用性能.     

切削刀具表面TiCN涂层的研究现状与发展

近年来,我国汽车产业迅猛发展,汽车机械零部件的需求给我国切削加工业带来了发展机遇和挑战.汽车安全性和舒适性的要求,国家节能减排、绿色制造的发展战略,指引切削技术向高速、高效、高精、绿色、智能方向发展,对刀具材料的使用性能也提出了更高要求.TiCN涂层刀具因具有高硬度和高耐磨性被大量应用,尤其是在有色金属及合金的切削加工上具有明显优势.综述了TiCN涂层的微观结构,指出C原子具有细化晶粒和抑制柱状晶形成的作用,涂层的结晶度和择优取向随C含量的改变而变化.总结了TiCN涂层的主要性能特点,包括硬度和致硬机理、耐磨性和减摩机理、热稳定性和热失效机制.介绍了TiCN涂层的沉积原理,指出各种制备方法的优缺点和关键工艺参数.分析了以TiCN为基进行改性获得的涂层的国内外最新研究现状,提出对TiCN涂层进行多层化、多元化以及纳米多层化,是进一步提高该涂层在高温条件下综合性能的方法,也是该涂层为适应高速切削、干式切削等新切削技术要求的发展方向.     

YT5硬质合金耐磨损实验中的热电热研究

切削工具的使用寿命直接影响加工质量和生产效率，硬质合金切削刀具的热电性能直接影响其使用寿命。本文通过切削实验研究了ＹＴ５硬质合金刀片耐磨性与热电热的关系，并建立了相应的实验相关性公式，找出了ＹＴ５硬质合金刀片的热电热对耐磨性的影响规律。     

精密切削纯铁材料硬质合金刀具刃口磨损特征演化

为研究纯铁材料精密切削时刀具刃口磨损特征演化规律,以涂层硬质合金刀具为研究对象进行纯铁材料精密切削试验。结果表明：涂层硬质合金刀具精密切削纯铁材料的磨损特征有后刀面均匀磨损带、主沟槽磨损、副沟槽磨损、刀尖磨损;主、副沟槽磨损长度都随着切削时间增加而增大且大于后刀面磨损量,沟槽磨损深度与沟槽磨损长度大致呈线性正相关;刀尖退化与后刀面磨损变化规律相互对应,切削初期磨损率大,随后磨损缓慢。     

钛合金车削温度的仿真与试验研究

基于ABAQUS建立了YG8硬质合金刀具车削TC4钛合金的二维切削仿真模型,通过红外热成像仪测得的切削温度对仿真模型得到的切削温度进行了验证,并研究了该模型刀具前刀面切削温度与切削速度、进给量、刀具前角及刀具后角的关系,通过中心复合试验得到了切削温度关于切削速度、进给量和刀具前角的预报模型。研究表明:仿真得到的切削温度与试验得到的切削温度相差小于10%;在一定范围内,随着切削速度和进给量的增加,切削温度均增加;随着刀具前角的增加,切削温度减小;随着刀具后角的增加,切削温度变化幅度不大;切削速度对切削温度的影响最为显著。     

超细晶硬质合金刀具车削不锈钢的切削温度研究

超细晶硬质合金刀具由于具有更高的硬度和抗弯强度,可以满足现代制造业的更高要求,在难加工材料高速切削领域显示出明显优势。在不锈钢材料的加工过程中,切削温度对刀具的磨损有极大的影响,而多数实验方法很难测得刀具表面具体的温度分布。借助DEFORM仿真分析软件,模拟超细晶硬质合金刀具对304不锈钢的车削过程;依据正交试验方法,分析切削用量三要素切削速度、进给量和背吃刀量对刀具温度的影响规律;通过实际车削实验与仿真结果进行比较,并与普通晶粒硬质合金刀具进行对比。结果表明:与普通晶粒硬质合金刀具加工相似,切削速度对超细晶粒硬质合金刀具温度的影响程度最大,其次是进给量,最后是背吃刀量;超细晶粒硬质合金比普通晶粒硬质合金刀具具有更好的散热性,尤其在较高速度条件下切削,优势更加明显。     

硬质合金刀具高速干铣削Ti6Al4V刀具寿命研究及切削参数优化

Ti6Al4V是典型的难加工材料,切削效率低,刀具磨损严重。文章对硬质合金刀具在高速范围内干铣削Ti6Al4V进行了正交试验,获得了干切削状态下铣削刀具寿命的经验公式,并利用扫描电镜（SEM）和能谱分析（EDS）研究了铣削刀具的磨损形态和磨损机理,粘结、扩散及氧化是硬质合金刀具的主要磨损机理。最后,利用等寿命-效率响应曲面法,对硬质合金刀具在干切削状态下铣削Ti6Al4V的切削参数进行了优化,在效率不变的情况下,适当降低切削速度,增大切削深度,可以提高刀具寿命。试验刀具的切削参数优化结果为：切削速度40—60m／min、轴向切削深度0．5—1mm、径向切深7—10mm、进给量0．07—0．1mm／r,在建议切削参数下刀具寿命约在30—50min。     

连续和间断TiN涂层的氮化硅基陶瓷切削工具的耐磨性能

明显提高切削工具的寿命，扩大其使用范围以及强化材料的加工规范可通过涂覆保护涂层来达到。应用最广泛的是对高速钢和硬质合金进行耐磨涂层，而在工具陶瓷上则应用较少。氮化硅基陶瓷刀具在高速切削的条件下会与钢发生积极的反应，从而产生明显的扩散磨损。因此，当切削最硬的合金工具钢时，在非氧化物陶瓷刀具上进行耐磨涂层是特别适合的。     

PCBN刀具的新进展及趋势展望

1．PCIIN刀具材料的优势 在机械加工制造领域，切削加工技术已经进入以高速铣削、CNC多功能切削、微细形状／超精切削等为代表的变革创新时期。与此同时，切削刀具的变革创新也有了新的进展。现阶段的刀具材料以涂层硬质合金为主导，最高切削速度范围300～600m／min。可以预测，今后切削高速化的发展会更加迅猛，当1000m／min以上的超高速切削时代到来时，PCBN将成为最强有力的刀具材料，具有极大的优势。     

高速切削刀具材料研究与选用

介绍了高速切削技术的概念,探讨了高速切削刀具材料的性能要求,重点对硬质合金、金刚石、陶瓷和立方碳化硼等高速切削刀具材料进行了研究.最后给出了高速切削刀具材料的选用方法.     

织构刀具高速干式切削Al7075-T6的性能研究

表面微织构能够改善刀具的切削性能。为了研究织构刀具高速干切削Al7075-T6时织构参数对切削性能的影响,利用仿真软件建立正交二维切削仿真模型。对比了所选织构参数范围内的最优织构刀具与无织构刀具的主切削力、刀具温度、刀具应力,分析了织构参数对主切削力的影响程度。结果表明:合理的织构参数,可以减小刀具的主切削力,使刀具表现出更好的温度及应力分布梯度;所选织构参数范围内,织构宽度为60μm、织构间距为90μm、织构深度为30μm、织构刃边距为100μm的织构刀具切削性能最好;织构参数对主切削力影响程度从大到小依次为织构刃边距、织构宽度、织构间距、织构深度。     

基于微磨削方法的微织构刀具制备与切削性能研究

目的研究表面微织构对硬质合金刀具切削性能的影响。方法采用微磨削方法在硬质合金刀具前刀面加工出具有不同结构参数的横向、纵向和交叉微织构,通过AL6061切削试验和有限元切削仿真,研究表面微织构对硬质合金刀具的切削温度及刀具磨损的影响。结果采用V形金刚石砂轮微磨削方法能够加工出几何形状规则且表面质量良好的表面微织构。与无织构刀具相比,微织构刀具的切削温度明显降低,高温区域明显减少,其中横向织构刀具降温效果最为显著。微织构刀具的切削温度随沟槽间距的增大而升高,沟槽间距为150μm时,切削温度最低。表面微织构能够有效减轻刀具前刀面的粘结磨损,横向织构刀具减摩抗粘效果最好,且采用较小的沟槽间距更利于减轻刀具的粘结磨损。随着切削速度的增加,表面微织构的抗粘结作用更加明显,当切削速度为150 m/min时,沟槽间距为150μm的横向织构刀具的切屑粘结面积最小。结论在横向、纵向和交叉织构刀具中,沟槽间距为150μm的横向织构刀具切削性能最好,即降温效果、抗粘结性能最为显著。     

Effects of cutting geometry in turning with TiN-coated tools

The effects of cutting tool geometry on the performance of TiN-coated high-speed steel tools were studied. Turning tests were carried out with inserts made of conventional and powder metallurgical HSS. The workpiece material was a case hardening steel with a hardness of 170 HB. Two different cutting geometries were used. In addition to altering the cutting angles, the effect of honing the cutting edge before coating was studied. The results showed clearly that even small changes in the tool angles affect the performance of the TiN-coated tool. Honing the cutting edge significantly increased wear resistance by improving the edge strength and reducing microchipping. On the basis of the results the modification of cutting tool geometry for hard coatings is discussed.     

Wear and cutting performance of diamond composite material-a comparison with tungsten carbide

A series of wear and rock cutting tests were undertaken to assess the wear and cutting performance of a thermally stable diamond composite (TSDC). The wear tests were conducted on a newly designed wear testing rig in which a rotating aluminium oxide grinding wheel is turned (also known as machined) by the testing tool element.The rock cutting tests were performed on a linear rock-cutting planer. The thrust and cutting forces acting on the tool were measured during these tests. A tungsten carbide element was also studied for comparative purposes. The wear coefficients of both materials were used to evaluate wear performance while cutting performance was assessed by tool wear and the rates of increase in forces with cutting distance.     

An application of the finite element method to the prediction of cutting tool performance

In metal cutting tools the are close to the tool point is the single most important region and conditions at the tool point must be carefully examined if improvements in tool performance, through changes in tool design and material, are to be achieved. The paper describes an analysis of cutting tool performance through a determination of the stress distribution within, and at the boundaries of, the tool wedge. The stressanalysis was based on a two-dimensional model as encountered in orthogonal cutting, using a range of cutting geometries including tools with double rake angles. A finite element technique was employed which can be effectively utilised in the solution of metal cutting problems once the boundary conditions have been established. The results presented demonstrate the significance of the chosen boundary conditions to the analysis of metal cutting. Finally it is argued that the deformation of the cutting edge, especially at the clearance face under the stress field set up in the tool, may well be a determining factor in establishing tool life as based on the flank wear criterion.     

有机物切割刀具用钢的研究和应用

通过分析有机物切割刀具用钢的使用性能及设计要求,设计并生产了一种新型有机物切削刀具用的高碳低合金钢,采用了粒子相钉扎晶界细化晶粒及低温二次硬化技术,使该钢的硬度可达68～72 HRC,并有一定韧性与之匹配.该钢已经应用在卷烟厂制作解把刀、打叶刀、切丝刀等刀具,以及其他有机物切削刀具,使用性能及寿命均高于同类型钢种.     

有限元仿真预测高温合金切槽刀具寿命的初步探讨

通过分析切槽刀具在切槽过程中的加工难点,结合难加工材料高温合金Inconel 718的材料特性,提出了一种新的刀具设计思路,设计了一种新断屑槽结构的切槽刀具,该断屑槽的特点是凸起部位由平滑过渡的曲面构成。对比刀片为市售国外同类产品是采用尖锐棱角构成的断屑槽。采用DEFORM软件对两种刀片进行有限元切削仿真和切削试验结果表明,新的切槽刀具的综合性能优于国外同类产品,且仿真评价与切削实验结果基本一致,说明采用有限元仿真预测不同方案的高温合金切槽刀具寿命的高低是基本可行的,可以初步应用到切槽刀具的结构设计中来。     

Cutting performance of PVD-coated carbide and CBN tools in hardmilling

In this study, cutting performance of CBN tools and PVD-coated carbide tools in end-milling of hardened steel was investigated. In high-speed dry hardmilling, two types of CBN tools were applied: the CBN-rich type and an ordinary one. In the case of relatively low-speed milling, on the other hand, a few coated carbide tools were selected where four kinds of coating films, TiN, TiCN, TiAlN and multi-layered TiAlN/AlCrN, were deposited on the K10 and P30 grade carbide. The cutting performance was mainly evaluated by tool wear, cutting temperature, cutting force and surface roughness. In dry cutting of hardened carbon steel with the ordinary CBN tool, the cutting tool temperature rose rapidly with increase in cutting speed; and tool temperature reached approximately 850 °C at the cutting speed of 600 m/min. In the case of the CBN-rich tool, the cutting temperature decreased by 50 °C or more because of its high thermal conductivity. It is remarkable that tool wear or damage on a cutting tool was not observed even when the cutting length was 156 m in both CBN tools. In the case of coated carbide tools, the temperatures of TiN-, TiCN- and TiAlN-coated carbide tools rose as cutting proceeded because of the progress of tool wear, but that of TiAlN/AlCrN-coated carbide tool hardly rose due to little tool wear. When the base material was K10 grade carbide, tool temperature was lower than that of P30 with any coating. The tool flank wear depends considerably on hardness and oxidizing temperature of the coating film.     

切削刀具PVD涂层技术的发展及应用

PVD涂层是利用蒸发、辉光放电等物理过程 ,在基材表面沉积出所需要的涂层的技术 ,通常采用的 PVD技术有蒸发镀膜、离子镀膜和溅射镀膜三大类 ,其中离子镀和溅射镀适合于对切削刀具进行超硬材料涂层。本文着重介绍了溅射镀技术及采用该技术生产的几种重要的涂层 ,结合实例介绍了它们的使用性能 ,并对 PVD涂层切削刀具技术的研究进展 ,工业化生产及应用现状进行了综述。     

CVD金刚石涂层刀具切削性能与磨损机理研究

针对普通刀具切削质量差、刀具耐用度低等问题,对CVD涂层刀具制备方法及切削性能进行研究。首先以硬质合金刀具为基体通过CVD方法制备金刚石涂层,分析涂层表面形貌。然后在不同条件下进行铝合金材料的干式切削试验,分析金刚石涂层对切削力、切削温度以及工件表面粗糙度的影响规律。最后,通过对刀具磨损机理的分析,讨论涂层对刀具使用寿命的影响。研究结果表明,所制备的涂层刀具能够降低切削力和切削温度,大大提高刀具的切削性能和工件的表面质量,并能有效提高刀具使用寿命。