陶瓷刀具材料的现状与发展

本文阐述了陶瓷刀具材料的发展现状 ,着重论述了氧化铝系陶瓷和氮化硅系陶瓷材料技术。对陶瓷刀具材料的发展趋势进行了综述。指出超微粉刀具、复相陶瓷刀具、涂层刀具及金属陶瓷是陶瓷刀具材料的研究方向。     

陶瓷刀具材料及应用技术

陶瓷刀具具有优良的切削性能，在金属切削加工中越来越受到重视。本文对陶瓷刀具的种类、性能和应用进行了论述，并指出陶瓷刀具材料的发展方向。     

高速切削刀具材料的开发与选择

介绍了高速切削加工技术所使用的高速钢刀具、陶瓷刀具、涂层刀具、超硬刀具的性能特点及应用,探讨了选择刀具所考虑的因素。     

提高陶瓷刀具性能的技术途径与应用研究

陶瓷刀具具有优良的切削性能。对陶瓷刀具的种类、性能和应用进行了论述,指出了提高陶瓷刀具性能的发展方向。     

梯度功能陶瓷刀具材料的残余应力设计及制备

根据陶瓷刀具切割时刀楔内的应力分布规律及刀具损坏机理的分析,首次提出以陶瓷刀具材料的组成分布进行设计以及梯度的模型,通过对不同组成分布的刀具材料制备过程中的残余应力及刀具切削过程中的热应力,机械应力进行模拟,以残余应力与外加应力部分抵消为目标优化设计了梯度组成分布,按设计结果,采用粉末铺填－热压烧结工艺研制成功Ａｌ２Ｏ３／ＴｉＣ系梯度功能陶瓷刀具材料。     

Al2O3—TiB2陶瓷刀具材料的研制及其耐磨性能研究

本文研制成功了一种新型陶瓷刀具材料即Al_2O_3-Ti B_2陶瓷刀具材料。文中讨论了该材料的研制方法,力学性能和微观结构特点,并对该材料的磨损行为和磨损机理进行了研究。结果表明:Ti B_2粒子的弥散可以明显提高该材料的耐磨性。加工淬火钢时该材料的抗磨损能力明显优于Al_2O_3-TiC陶瓷刀具材料。Al_2O_3-Ti B_2陶瓷刀具材料的磨损过程主要受粘着、耕犁和微破损机制的控制。     

纳米材料在陶瓷刀具中的应用现状

简述了纳米材料的基本性质,介绍了几种典型的纳米材料在陶瓷刀具中的应用,并探究其对陶瓷刀具材料的作用原理.同时也指出了纳米材料在陶瓷刀具中的应用要注意的技术问题以及纳米技术在陶瓷刀具中应用研究的方向.     

Al2O3／SiCW陶瓷刀具材料中晶须的取向对其力学和切削性能的影响

Ａｌ２Ｏ３／ＳｉＣＷ陶瓷刀具材料由于热压过程的影响，造成晶须在基体中定向排布于垂直热压方向的平面上，因此不同方向的补强、增韧效果有所差异。本工作测量了Ａｌ２Ｏ３／ＳｉＣＷ陶瓷刀具材料不同方向上的断裂韧性和抗弯强度，分析了晶须的取向对该陶瓷刀具材料力学性能的影响。切削试验表明晶须的取向对晶须增韧陶瓷刀具材料的磨损和破损性能有较好的影响。根据切削加工过程中刀具的受力特点，提出了有利于切削加工的刀具前、     

浅析陶瓷刀具高速切削可靠性的影响因素

简要介绍了影响陶瓷刀具高速切削可靠性的几种因素，阐明了陶瓷刀具与被加工材料的匹配性要求和陶瓷刀具几何角度的选择，以充分发挥陶瓷刀具的工效高、使用寿命长和加工质量好等优点。     

两类陶瓷刀具的现状、性能与应用

综述了氧化铝系和氮化硅系两类陶瓷刀具的发展现状,阐述了两类陶瓷刀具的力学性能与切削性能,论述了两类陶瓷刀具的特点、加工范围以及合适的切削加工用量,提出了刀具使用过程中的一些注意问题。     

技术创新助推新型陶瓷刀具在机加工中的应用优势凸显

随着新技术革命的发展,要求不断提高切削加工生产率和降低生产成本,特别是数控机床的发展,要求开发比硬质合金刀具切速更高、更耐磨的新型刀具。针对新型陶瓷切削刀具的应用前景广阔,分析了切削刀具材料的种类及其特点,研究了新型陶瓷切削刀具的性能突显,介绍了新型陶瓷切削刀具运用实例,提出了陶瓷切削刀具材料的研发应用方向。     

Analysis of cutting responses of Sialon ceramic tools in high-speed milling of FGH96 superalloys

Powder metallurgy superalloy FGH96 is being extensively used to fabricate the hot section of the aeronautic and astronautic turbine engines owing to its superior mechanical properties maintained at high-temperature environments. However, machining such a difficult-to-cut material entails high cutting forces, excessive cutting temperatures and serious tool wear. Although Sialon ceramic tools have been successfully employed in the turning and milling processes for the Inconel 718, their application for the machining of powder metallurgy superalloys is very limited. In the current work, a series of high-speed milling trials were conducted to examine the influences of the milling parameters on the cutting response and tool wear mechanisms during the milling of FGH96 with Sialon ceramic mills under dry conditions. The milling forces and machining temperatures were studied with respect to the used process parameters. The quality of cut surfaces and wear signatures of ceramic tools were also discussed. Results indicate that the resultant cutting forces only decrease until the cutting speed exceeds 315 m/min. Furthermore, the Sialon tools seem more suitable for the rough machining of FGH96 considering the surface finish and large residual tensile stress existing on the milled surface. Finally, the adhesion wear is the primary wear mode occurring at the flank surface, while the edge chipping and flaking dominate the failure of the tool rake surface.     

Medium Density Fiberboard Machining and Wear Behavior of Injection‐Molded Ceramic Composite Wood Cutting Tools

Wear behavior of four different ceramic composite cutting tools was studied in peripheral milling of medium density fiberboard. Tools were previously manufactured by near net‐shape ceramic injection molding with subsequent debindering and sintering. Cutting edge rounding and recession were investigated for defined cutting parameters and distinct cutting distances. Cutting forces were measured dependent on tool material and feed travel. Wear characteristics of ceramic cutting tools were investigated by SEM. Ceramic injection‐molded tools were successfully applied in wood‐machining operations. Wear mechanisms changed with different ceramic composites used. Results of microchamfered ACY tools showed superior lifetime compared with standard WC–Co tools.     

The cutting performance of Al2O3 and Si3N4 ceramic cutting tools in the milling plywood

ABSTRACT

This research focuses on the cutting performance of Al₂O₃ and Si₃N₄ ceramic cutting tools in up-milling plywood, the results of which are as follows. First, whether the tool material is Al₂O₃ or Si₃N₄ ceramic, the cutting forces at low-speed cutting were less than those at high-speed cutting, and the machining quality at low-speed cutting was greater than that at high-speed cutting. Then, whether at low- or high-speed cutting, the cutting forces of Al₂O₃ cutting tools were higher than those of Si₃N₄ cutting tools, and the machining quality of plywood milled by Al₂O₃ ceramic cutting tools was poorer than that milled by Si₃N₄ ceramic cutting tools. Finally, Si₃N₄ ceramic cutting tools were more suitable to machine the wooden productions with much glue content than Al₂O₃ ceramic cutting tools for the better machined quality.     

Injection molding of ceramic cutting tools for wood-based materials

In this study a mutable mold for ceramic cutting tools with inserts of different cutting angles and two different injection positions was designed. Three alumina-based ceramic feedstocks with different types and amount of second phases were developed. A mold filling study was carried out for both sprue positions in order to prove the molding behavior of the feedstock and the functionality of the mold. Debindering and sintering of molded green parts was arranged for each composition, respectively. Mechanical properties, microstructure and achieved cutting edge sharpness of produced tools were investigated. Results show that the mold design and injection molding process play a key role in order to manufacture cutting tools of best possible sharpness enabling a wood machining process. Feedstocks exhibit a good mold filling behavior resulting in comparatively sharp cutting edges of ≈10 μm after sintering. Mechanical properties show high potential for application of wood machining cutting tools.     

Friction and wear behavior of microwave sintered Al2O3/TiC/GPLs ceramic sliding against bearing steel and their cutting performance in dry turning of hardened steel

An Al₂O₃/TiC/GPLs (ATG) composite ceramic tool material was fabricated by microwave sintering. The tribological properties of ATG during sliding against GCr15 bearing steel were studied, to investigate the effects of sliding speed and normal load on the friction coefficient and wear rate. In addition, the cutting performance of ATG tools for machining of hardened alloy 40Cr steel was experimentally studied and compared with those of commercial tools. The results showed that the added graphene platelets enhanced the wear resistance and reduced the friction coefficient of the tool material. Furthermore, upon adding graphene platelets, the ability of the tools to resist breakage and their cutting depth improved. The cutting length of the microwave- sintered ATG ceramic tools was approximately 125% higher than that of hot-pressed ceramic tools and 174% higher than that of cemented carbide tools.     

Self-lubricating behaviors of Al2O3/TiB2 ceramic tools in dry high-speed machining of hardened steel

In this paper, Al₂O₃/TiB₂ ceramic cutting tools with different TiB₂ content were produced by hot pressing. The fundamental properties of these ceramic cutting tools were examined. Dry high-speed machining tests were carried out on hardened steel. The tool wear, the cutting temperature, the cutting forces, and the friction coefficient between the tool and the chip were measured. It was shown that both the wear rates and the friction coefficient at the tool–chip interface of Al₂O₃/TiB₂ ceramic cutting tools in dry high-speed machining of hardened steel were reduced compared with that of in low-speed machining. The mechanisms responsible were determined to be the formation of a self-lubricating oxide film on the tool–chip interface owing to the tribological–chemical reaction by the elevated cutting temperature. The composition of the self-lubricating film was found to be the oxidation product of TiB₂ grains, which serves as lubricating additive on the wear track of the tool rake face. The appearance of this self-lubricating oxide film contributed to the improvement in wear resistance and the decrease of the friction coefficient. This action was even more effective with higher TiB₂ content. Cutting speed was found to have a profound effect on the self-lubricating behavior. In dry low-speed machining of hardened steel, the Al₂O₃/TiB₂ tools showed mainly adhesive and abrasive wear. While in dry high-speed machining, oxidation wear of the ceramic tools was the dominant mechanism due to the very high cutting temperature. No oxide film was formed on the tool–chip interface while machining in nitrogen atmosphere, and the tool wear resistance was correspondingly decreased.     

Performance of lightweight coated oxide ceramic composites for industrial high speed wood cutting tools: A step closer to market

The introduction of lightweight cutting tips in industrial wood machining could lead to machining at much higher speeds and thus greatly increase efficiency. One possible way to achieve this is through lightweight ceramic composites. An Al₂O₃ ceramic matrix was selected and reinforced with particles resulting in a density of approximately one quarter of the currently used heavy tungsten carbide tools (density of >15 g/cm³). Furthermore, a coating was applied to the ceramic cutting tools in order to increase the stability of the cutting edge. A combination of reduced coefficient of friction, frictional forces and a resulting decrease in temperature can lead to a reduction in chipping at the cutting tip. Chipping has always been the major drawback of ceramic cutting tools for industrial wood cutting. A ceramic composite containing 25 vol% of submicron and nano sized SiC particles shows good mechanical properties with HV₂=21.5 GPa and K_Ic=4.5 MPa m^1/2. This composition performed very well in industrial cutting trials on laminated beech. The cutting performance was increased further by use of an industrially available coating on the tools. The quality of the cut wood surface has always been difficult to characterize when comparing cutting tool materials and is often performed qualitatively by experienced carpenters by touch. The surface quality of the machined laminated beech was for the first time quantitatively characterized using Gelsight 2.5D tactile sensing.     

Investigation of novel multiscale textures for the enhancement of the cutting performance of Al2O3/TiC ceramic cutting tools

Currently, the high temperature and severe friction conditions at the tool-chip interface are the main reasons for ceramic tool wear failures. Surface texturing as a geometric extension for cutting tools is a promising way to extend their service life. In this study, a novel type of multiscale texture was developed, and its effect on the cutting performance of an Al₂O₃/TiC ceramic cutting tool while machining AISI H13 steel was explored in a conventional cooling environment. The cutting force, cutting temperature, and tool wear morphology were investigated at cutting velocities ranging from 80 to 249 m/min. Microgroove textured Al₂O₃/TiC ceramic tools were prepared for comparison. The results show that the structure of the multiscale textures maintained good integrity over the range of cutting velocities. Thus, the synergistic effect of the microscale and nanoscale textures promoted the introduction and permeation of the cutting fluid. Therefore, the multiscale textures effectively enhanced the cutting performance of the Al₂O₃/TiC ceramic tools.