离子镀TiCN和TiN工具涂层的微结构与切削性能

采用电弧离子镀技术在硬质合金铣刀和钻头上镀覆了TiCN和TiN涂层,研究并比较了两种涂层的微结构与力学性能,以及涂层铣刀的高速切削性能和涂层钻头的切削性能。结果表明,TiCN和TiN涂层同为单相的Na-Cl型结构,并都呈现(111)择优取向的柱状晶,TiCN涂层的硬度为34.6GPa,远高于TiN涂层25.1GPa的硬度。在高速铣削条件下,TiCN涂层铣刀的后刀面磨损速率仅为TiN涂层铣刀的约三分之一。TiCN涂层钻头在钻孔数为TiN涂层钻头两倍时的磨损量仍低于TiN涂层钻头。TiCN涂层的高硬度及在较高切削线速度下的减摩作用是这种涂层刀具寿命提高的重要原因。     

TiAlN涂层刀具的发展与应用

TiAlN涂层作为一种新型涂层材料,具有硬度高、氧化温度高、热硬性好、附着力强、摩擦系数小、导热率低等优良特性,有望部分或完全替代TiN,尤其适用于高速切削。文中对国内外TiAlN涂层刀具的发展与应用状况进行了综合评述,并着重分析了TiAlN涂层工艺及其切削性能。     

TiAlN涂层的制备及其高速铣削淬硬钢的切削性能研究

利用电弧离子镀在硬质合金刀具上沉积TiAlN涂层,该涂层由TiN过渡层和TiAlN涂层组成。采用扫描电子显微镜(SEM)、纳米硬度计和球盘摩擦测试等方法对涂层的显微组织和力学性能进行分析表征。在干式切削条件下,通过高速铣削测试淬硬(Crl2MoV,62 HRC),对涂层的切削性能进行了研究。结果表明:沉积的TiAlN涂层硬度高达31GPa,能有效地提高硬质合金刀具的高速切削性能。并对相关磨损机制进行了讨论。     

硬质合金铣刀涂层性能的试验研究

针对涂层材料改善刀具切削性能这一问题,本文采用常速试验和高速试验的方法,对比分析了七种涂层材料对铣刀切削性能的改善程度。试验结果表明:涂层性能优越与否与切削速度有很大关系,AlCrN和TiAlCN涂层铣刀更适合高速切削;而AlTiN涂层铣刀不适合高速切削;TiN涂层铣刀无论在常速和高速切削时性能均表现不佳,高速切削时磨损相对更快;CrN+TiN复合涂层抗氧化能力较好,但抗磨能力相对较差。     

涂层钻头加工不锈钢磨损机理研究

研究了TiN、TiAlN、TiCN三种高速钢涂层专用麻花钻头钻削加工1Cr18NigTi奥氏体不锈钢时的刀具寿命以及刀具表面涂层的磨损特性。通过研究刀具寿命以及对刀具前刀面涂层磨损形态和元素成分的变化规律，揭示了三种涂层钻头的磨损机理。结果表明：在中低速、湿切削的情况下，TiCN涂层要优于TiAlN涂层，明显优于TiN涂层；TiCN涂层高速钢专用钻头较TiAlN、TiN涂层高速钢专用钻头更加适合不锈钢的钻削加工。研究结果对提高不锈钢钻削加工效率与加工质量具有重要意义。     

TiAlN涂层与TiCN涂层硬质合金刀具性能对比

利用TiAlN涂层与TiCN涂层硬质合金刀具对模具钢进行切削,探讨其切削性能.通过多次试验,将TiAlN涂层与TiCN涂层硬质合金刀具的使用寿命作了比较.研究结果表明,TiAlN涂层刀具在提高工件切削性能方面效果是显著的,并大幅提高了刀具的耐用度.     

不同涂层刀具铣削退火H13钢加工性能研究

为了研究退火后的H13钢的切削加工性能,采用多种Ti化合物涂层刀具进行铣削退火H13钢试验,分析了不用的涂层材料刀具与切削力、切屑形态以及刀具磨损状况之间的关系。研究得出:TiAlN涂层刀具受到三个方向的力比TiN涂层刀具以及TiC涂层刀具受到的力小;TiAlN涂层刀具切削后后刀面磨损较小,TiN涂层刀具次之,TiC涂层刀具后刀面损伤面积最大;TiAlN涂层刀具切削产生的切屑大多呈现细长卷曲的形状,且切屑长度适中,切削性能最佳。     

新型涂层刀具干式铣削加工SKD11切削性能研究

具有高硬度、耐高温、高耐磨性能和良好韧性的涂层刀具在干式切削加工中的应用越来越多,不同涂层刀具的应用场合及先进涂层的开发已成为目前涂层刀具技术研究的重点。本文基于TiAlN、AlTiN和TiAlN+WC/C三种涂层刀具在干式铣削加工SKD11时的切削力、切削温度和刀具磨损等物理量,对其切削性能作了详细分析。研究结果表明:在干铣加工SKD11时TiAlN+WC/C涂层刀具和AlTiN涂层刀具优于TiAlN涂层刀具,其中AlTiN涂层刀具的涂层材料硬度最高,而且在切削高温影响下生成Al2O3的薄膜层能延长该涂层刀具的寿命;TiAlN+WC/C涂层刀具的切削力小、刀具耐用度高,是干式铣削加工模具钢SKD11的理想刀具。     

不同涂层刀具切削淬硬H13钢加工性能研究

为了研究不同涂层刀具切削淬硬H13钢的切削性能,进行了多层Ti化合物涂层、TiAlN涂层以及MTTiCN厚Al_2O_3TiN涂层材料刀具车削加工淬硬H13钢试验,分析了不同的涂层材料刀具与切削力、切削温度、涂层刀具磨损以及刀具寿命的关系。研究得出:多层Ti化合物涂层刀具受到三个方向的力都大于其它两种涂层的刀具,而且切削温度最高;用TiAlN涂层刀具切削时温度最低;切削过程中三种刀具后刀面磨损程度不同,发现多层Ti化合物涂层刀具磨损最为严重,寿命最短;MT-TiCN厚Al_2O_3Ti N涂层材料刀具比多层Ti化合物涂层刀具寿命长30%;TiAlN涂层刀具的切削寿命最长比多层Ti化合物涂层刀具寿命长45%。     

坚韧的TiCN刀具涂层

新一代的耐磨涂层TiCN是由多重涂层结合而成,总厚度为0.002mm,其硬度明显高于TiN涂层。而且TiCN涂层可以最大限度地防止磨料磨损并具有出色的热化学稳定性和卓越的润滑性。 Niagara Cutter公司根据四种不同类型(直径均为15.9mm)无涂层高速钢、TiN涂层高速钢、TiCN涂层高速钢和整体硬质合金的四槽端铣刀所进行的切削试验表明,这四种刀具材料铣刀所达到的切削速度分别为425、900、1200和1500r/min。试验工件材料为4140钢,零件硬度为HB275。还有一厂家将TiCN涂层刀具与高速钢刀的切削     

Tribological evaluation of TiN and TiAlN coated PM-HSS gear cutter when machining 19MnCr5 steel

Two PVD coated powder metallurgy high speed steel (PM-HSS) gear cutters were investigated when machining helical gears made from AISI 19MnCr5 steel with hardness between 140 and 180 HV. Machining trials were carried out with gear cutters coated with TiAlN (nano layers) and TiN (mono layer). Crater and flank wears were measured and analysed after all the machining trials. Analyses of the worn tools show that the TiAlN coated gear cutter performed better than the TiN coated gear cutter. This can be attributed to its nano layers and the higher hardness of the TiAlN coating. The dominant tool wear mechanisms were adhesion, abrasion, delaminating of the coating layer and chipping of the cutting edge.     

Investigation of the performance of carbide cutting tools with hard coatings in hard milling based on the response surface methodology

Machining of hard materials has become a great challenge for several decades. One of the problems in this machining process is early tool wear, and this affects the machinability of hard materials. In order to increase machinability, cutting tools are widely coated with nanostructured physical vapor deposition hard coatings. The main characteristics of such advanced hard coatings are high microhardness and toughness as well as good adhesion to the substrate. In this paper, the influence of hard coatings (nanolayer AlTiN/TiN, multilayer nanocomposite TiAlSiN/TiSiN/TiAlN, and commercially available TiN/TiAlN) and cutting parameters (cutting speed, feed rate, and depth of cut) on cutting forces and surface roughness were investigated during face milling of AISI O2 cold work tool steel (～61 HRC). The experiments were conducted based on 3¹³ factorial design by response surface methodology, and response surface equations of cutting forces and surface roughness were obtained. In addition, the cutting forces obtained with the coated and uncoated tools were compared. The results showed that the interaction of coating type and depth of cut affects surface roughness. The hard coating type has no significant effect on cutting forces, while the cutting force F _z is approximately two times higher in the case of uncoated tool.     

High-Speed Machining of Malleable Cast Iron by Various Cutting Tools Coated by Physical Vapor Deposition

The coating material of a tool directly affects the efficiency and cost of machining malleable cast iron.However,the machining adaptability of various coating materials to malleable cast iron has been insufficiently researched.In this paper,turning tests were conducted on cemented carbide tools with different coatings(a thick TiN/TiAlN coating,a thin TiN/TiAlN coating,and a nanocomposite(nc)TiAlSiN coating).All coatings were applied by physical vapor deposi-tion.In a comparative study of chip morphology,cutting force,cutting temperature,specific cutting energy,tool wear,and surface roughness,this study analyzed the cutting characteristics of the tools coated with various materials,and established the relationship between the cutting parameters and machining objectives.The results showed that in malleable cast iron machining,the coating material significantly affects the cutting performance of the tool.Among the three tools,the nc-TiAlSiN-coated carbide tool achieved the minimum cutting force,the lowest cutting tempera-ture,least tool wear,longest tool life,and best surface quality.Moreover,in comparisons between cemented-carbide and compacted-graphite cast iron machined under the same conditions,the wear mechanism of the coated tools was found to depend on the cast iron being machined.Therefore,the performance requirements of a tool depend on multiple factors,and selecting an appropriately coated tool for a particular cast iron material is essential.     

钛合金铣削加工的PVD涂层适应性研究

利用电弧法沉积制备Al Cr N、Al Cr Si N、Al Cr N/Ti Al N、Al Cr N/Ti Si N四种用于钛合金切削加工涂层,研究了涂层的基本特性及切削使用效果。结果表明,Al Cr N涂层呈柱状生长,通过添加Si等元素或采用多层交替沉积有利于形成细化晶粒组织,提升涂层纳米硬度。切削试验表明,在低速铣削钛合金TC4时,Al Cr N/Ti Al N复合涂层表现最好。在较高速铣削时,四种涂层的刀具表现性能接近。     

硬质合金刀具高能离子源增强多弧镀AlCrTiSiN梯度涂层制备及性能研究

采用离子源增强的多弧离子镀新技术,在硬质合金刀具表面制备了不同含Si层梯度结构的AlCrTiSiN梯度涂层,并对涂层组织结构、残余应力、结合强度、摩擦磨损以及铣削和钻削加工灰铸铁性能进行了详细的研究。结果表明：不同含Si层梯度结构的AlCrTiSiN涂层主要由固溶的(Al,Cr) N、(Al,Ti) N相和非晶态Si₃N₄相组成。其中,含Si层梯度变化最缓和的G3(Gradient 3)涂层具有较高的结合强度,较低的残余压应力、摩擦因数和磨损率。铣削和钻削试验显示,涂层刀具的切削磨损机理主要表现为磨粒磨损和粘着磨损。G3涂层降低了磨粒磨损,其刀具的铣削和钻削寿命均最高,这主要得益于其含Si层的梯度设计、适当的压应力(-3.8 GPa)以及良好的膜基结合强度。研究结果表明,通过对含Si层进行梯度设计可显著提高涂层刀具的切削性能。     

Wear behavior and cutting performance of nanostructured hard coatings on cemented carbide cutting tools in hard milling

The influence of nanolayer AlTiN/TiN and multilayer nanocomposite TiAlSiN/TiSiN/TiAlN hard coatings on the wear behavior and cutting performance of carbide cutting tools was investigated in face milling of hardened AISI O2 cold work tool steel (∼58 HRC) at dry conditions. Characterization of the coatings was performed using nanoindentation, scratch test, reciprocating multi-pass wear test. The chips forming during cutting process were also analyzed. Results showed that abrasive and oxidation wear are dominant tool failures. The nanolayer AlTiN/TiN coating gives the best adhesion to the substrate, the best wear resistance in machining and thus provides the longest lifetime with carbide inserts.     

Monitoring of Wear Characteristics of TiN and TiAlN Coatings at Long Sliding Distances

TiN and TiAlN thin hard coatings have been widely applied on machine components and cutting tools to increase their wear resistance. These coatings have different wear behaviors, and determination of their wear characteristics in high-temperature and high-speed applications has great importance in the selection of suitable coating material to application. In this article, the wear behavior of single-layer TiN and TiAlN coatings was investigated at higher sliding speed and higher sliding distances than those in the literature. The coatings were deposited on AISI D2 cold-worked tool steel substrates using a magnetron sputtering system. The wear tests were performed at a sliding speed of 45 cm/s using a ball-on-disc method, and the wear area was investigated at seven different sliding distances (36–1,416 m). An Al₂O₃ ball was used as the counterpart material. The wear evolution was monitored using a confocal optical microscope and surface profilometer after each sliding test. The coefficient of friction and coefficient of wear were recorded with increasing sliding distance. It was found that the wear rate of the TiAlN coating decreases with sliding distance and it is much lower than that of TiN coating at longer sliding distance. This is due to the Al₂O₃ film formation at high temperature in the contact zone. Both coatings give similar coefficient of friction data during sliding with a slight increase in that of the TiAlN coating at high sliding distances due to the increasing alumina formation. When considering all results, the TiAlN coating is more suitable for hard machining applications.