CVD Diamond Coatings for Machining

2006 ◽  
Vol 526 ◽  
pp. 55-60 ◽  
Author(s):  
D. Moulin ◽  
O. Raymond ◽  
P. Chevrier ◽  
Paul Lipiński ◽  
Thierry Barre
Keyword(s):  
High Performance ◽  
Metal Cutting ◽  
Thermal Stresses ◽  
Chemical Vapour ◽  
Surface Preparation ◽  
Deposition Process ◽  
Cvd Diamond ◽  
Tool Geometry ◽  
Diamond Coatings ◽  
Machined Surface

Machining of modern materials requires high performance tools. More than 60% of metal cutting tools used are coated to limit abrasive wear. As the harder material known to man, diamond and consequently Chemical Vapour Deposited (CVD) diamond coatings allow to increase performances of tungsten carbide tools, i.e. tool life, machined surface quality, and to decrease costs. However, CVD diamond coated tools quality is very dependent on the surface preparation as much as the fabrication process parameters. This paper aims to discuss the influence of pretreatments before deposition, and thermal stresses induced by the cooling operation. Diamond deposition process is described emphasizing the role of every step and its function. Some numerical simulations of the residual stresses at the interface are presented, enlightening that tool geometry is an important factor while using a coating, and that tools must be designed for the diamond coating.

scholarly journals Design and Development of a Three Component Milling Dynamometer

2021 ◽  
Vol 2070 (1) ◽  
pp. 012168
Author(s):  
Narender Maddela ◽  
Ch.Sai Kiran ◽  
Aluri Manoj ◽  
M. Kapila ◽  
B. Swapna ◽  
...  
Keyword(s):  
Tool Wear ◽  
Heat Generation ◽  
Strain Gauge ◽  
Cutting Forces ◽  
Metal Cutting ◽  
Strain Gauges ◽  
Tool Geometry ◽  
Work Piece ◽  
Design And Development ◽  
Machined Surface

Abstract The cutting forces that are generated during metal cutting influence the work piece precision, tool wear, the nature of the machined surface, and heat generation. These cutting forces can be measured analytically however; precise outcomes may not be expected due to its included stresses, parameters of cutting, and the perplexing tool geometry. Henceforth the exploratory estimation of cutting forces is fundamental. For this reason, a milling dynamometer of three-segment is structured, created, and tried to gauge the three cutting forces which are produced during the operation of milling strain gauges can be utilized to quantify dynamic and static cutting forces through milling dynamometer. During the process of metal cutting, a dynamometer that is based on strain gauge is fit for estimating three-force segments. The dynamometer was designed based on the octagonal ring principle. The octagonal rings orientation and location of strain gauges have resolved to expand affectability and to limit cross-affectability.

Hochleistungsbohrwerkzeuge für CFK*/High performance drilling tools for CFRP – Wear and performance of CVD-diamond coatings

2019 ◽  
Vol 109 (01-02) ◽  
pp. 35-39
Author(s):  
E. Uhlmann ◽  
W. Reimers ◽  
K. Brömmelhoff ◽  
G. Christiansen
Keyword(s):  
Carbon Fiber ◽  
High Performance ◽  
Cvd Diamond ◽  
Carbon Fiber Reinforced Plastic ◽  
Diamond Coatings ◽  
Fiber Reinforced Plastic ◽  
Reinforced Plastic ◽  
Drilling Tools ◽  
Process Reliability ◽  
And Performance

Das Bearbeiten von Leichtbauwerkstoffen wie kohlefaserverstärkter Kunststoff (CFK) stellt aufgrund der hohen Anforderungen an die Werkstückqualität bei gleichzeitig hohem Werkzeugverschleiß eine Herausforderung für die Zerspanung dar. Für diesen Anwendungszweck wurden Bohrwerkzeuge mit verschiedenen CVD-Diamantbeschichtungen sowie Hartmetallsubstraten getestet und analysiert. Es wird die Bearbeitung von CFK wirtschaftlicher gestaltet. Die Prozesssicherheit und Leistungsfähigkeit wird gesteigert.   The machining of novel lightweight materials such as carbon fiber reinforced plastic (CFRP) is a challenge due to the high requirements regarding the workpiece quality while high tool wear occurs. For this purpose, drilling tools with different CVD diamond coatings and carbide substrates were tested and analyzed. The processing of CFRP is made more economical and the process reliability and efficiency are increased.

The Effect of the Cutting Parameters on the Machined Surface Roughness

2017 ◽  
Vol 260 ◽  
pp. 219-226 ◽  
Author(s):  
Viktors Gutakovskis ◽  
Eriks Gerins ◽  
Janis Rudzitis ◽  
Artis Kromanis
Keyword(s):  
Surface Roughness ◽  
Metal Cutting ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Cutting Parameters ◽  
Cutting Process ◽  
Tool Geometry ◽  
Machining Parameters ◽  
Machined Surface ◽  
Machined Surface Roughness

From the invention of turning machine or lathe, some engineers are trying to increase the turning productivity. The increase of productivity is following after the breakout in instrumental area, such as the hard alloy instrument and resistance to wear cutting surfaces. The potential of cutting speed has a certain limit. New steel marks and cutting surfaces types allow significantly increase cutting and turning speeds. For the most operation types the productivity increase begins from the feeding increase. But the increase of feeding goes together with machined surface result decreasement. Metal cutting with high feeding is one of the most actual problems in the increasing of manufacturing volume but there are some problems one of them is the cutting forces increasement and larger metal removal rate, which decrease the cutting tool life significantly. Increasing of manufacturing volume, going together with the cutting instrument technology and material evolution, such as the invention of the carbide cutting materials and wear resistant coatings such as TiC and Ti(C,N). Each of these coating have its own properties and functions in the metal cutting process. Together with this evolution the cutting tool geometry and machining parameters dependencies are researched. Traditionally for the decreasing the machining time of one part, the cutting parameters were increased, decreasing by this way the machining operation quantity. In our days the wear resistance of the cutting tools increasing and it is mostly used one or two machining operations (medium and fine finishing). The purpose of the topic is to represent the experimental results of the stainless steel turning process, using increased cutting speeds and feeding values, to develop advanced processing technology, using new modern coated cutting tools by CVD and PVD methods. After investigation of the machined surface roughness results, develop the mathematical model of the cutting process using higher values of the cutting parameters.

scholarly journals Interaction of Methane Concentration and Deposition Temperature in Atmospheric Laser Based CVD Diamond Deposition on Hard Metal

Coatings ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 537
Author(s):  
Markus Prieske ◽  
Sven Müller ◽  
Peer Woizeschke
Keyword(s):  
Coating Thickness ◽  
Deposition Temperature ◽  
Laser Scanning ◽  
Methane Concentration ◽  
Chemical Vapour ◽  
Cvd Diamond ◽  
Hard Metal ◽  
Process Temperature ◽  
Diamond Coatings ◽  
Methane Concentrations

For laser-based plasma chemical vapour deposition (CVD) of diamond on hard metal at atmospheric pressure, without a vacuum chamber, the interaction between the deposition temperature and the methane concentration has to be understood to adjust the coating thickness, deposition duration, and medium diamond crystal size. The hypothesis of this study is that a wider range of methane concentrations could be used to deposit microcrystalline diamond coatings due to the increasing etching and deposition rates with rising deposition temperatures. The deposition of the CVD diamond coatings was carried out on K10 hard metal substrates. The process temperature and the methane concentration were varied from 650 to 1100 °C and from 0.15% to 5.0%, respectively. The coatings were analysed by scanning electron and 3D laser-scanning confocal microscopy, energy dispersive X-ray and micro-Raman spectroscopy, as well as cryofracture-based microscopy analysis. The results showed that microcrystalline diamond coatings could be deposited in a wider range of methane concentrations when increasing the process temperature. The coating thickness saturates depending on the process temperature even though the methane concentration constantly increases. The coating thickness increases with an increasing deposition temperature until the cobalt diffusion hinders the deposition at the process temperature of 1100 °C.

scholarly journals Recent Advances in the Deposition of Diamond Coatings on Co-Cemented Tungsten Carbides

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
R. Polini ◽  
M. Barletta ◽  
G. Rubino ◽  
S. Vesco
Keyword(s):  
Chemical Vapour ◽  
Deposition Process ◽  
Tungsten Carbides ◽  
Diamond Coatings ◽  
Carbon Dissolution ◽  
Thermal Expansion Coefficients ◽  
Hard Metals ◽  
To Receive ◽  
And Diffusion

Co-cemented tungsten carbides, namely, hard metals are largely used to manufacture high wear resistant components in several manufacturing segments. Coating hard metals with superhard materials like diamond is of utmost interest as it can further extend their useful lifespan. The deposition of diamond coatings onto WC-Co can be extremely complicated as a result of poor adhesion. This can be essentially ascribed to (i) the mismatch in thermal expansion coefficients between diamond and WC-Co, at the typical high temperatures inside the chemical vapour deposition (CVD) chamber, generates large residual stresses at the interface; (ii) the role of surface Co inside the WC-Co matrix during diamond CVD, which promotes carbon dissolution and diffusion. The present investigation reviews the techniques by which Co-cemented tungsten carbides can be treated to make them prone to receive diamond coatings by CVD. Further, it proposes interesting ecofriendly and sustainable alternatives to further improve the diamond deposition process as well as the overall performance of the coated hard metals.

scholarly journals In-Situ Friction Monitoring of Self-Mated CVD Diamond Coatings Using Acoustic Emission

2006 ◽  
Vol 514-516 ◽  
pp. 749-753
Author(s):  
C.S. Abreu ◽  
Filipe J. Oliveira ◽  
J.R. Gomes ◽  
Manuel Belmonte ◽  
A.J.S. Fernandes ◽  
...  
Keyword(s):  
Acoustic Emission ◽  
Microwave Plasma ◽  
Normal Load ◽  
Chemical Vapour ◽  
Cvd Diamond ◽  
Ambient Atmosphere ◽  
Diamond Coatings ◽  
Ae Signal ◽  
State Regime

In-situ measurements of acoustic emission (AE) in self-mated tribological pairs of CVD diamond coated silicon nitride (Si3N4) were made with the purpose of investigating the relationship between AE signal and friction events. A good correlation is found between the energy dissipation/emission processes, therefore enabling the possibility of monitoring the different friction regimes occurring during the sliding contact of microcrystalline diamond (MCD) coatings. Deposition of MCD on flat and ball-shaped Si3N4 samples was accomplished using microwave plasma assisted chemical vapour deposition (MPCVD) with H2/CH4 gas mixtures. The friction behaviour of self-mated MCD coatings was assessed using a reciprocating ball-on-flat geometry. The tests were run in ambient atmosphere without lubrication, the frequency (1Hz) and stroke (6mm) were kept constant while the applied normal load varied in the range 10-80N. The microstructure, surface topography and roughness of the MCD coatings were characterised by SEM and AFM techniques. The diamond quality was assessed from micro-Raman spectroscopy. The friction evolution was characterised by a short running-in period where the main feature is a sharp peak reaching values as high as approximately 0.6 followed by a steady-state regime with very low values in the range 0.03-0.04.

scholarly journals Ultrathin, Lightweight, and Flexible CNT Buckypaper Enhanced Using MXenes for Electromagnetic Interference Shielding

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Rongliang Yang ◽  
Xuchun Gui ◽  
Li Yao ◽  
Qingmei Hu ◽  
Leilei Yang ◽  
...  
Keyword(s):  
Electromagnetic Interference ◽  
High Performance ◽  
Electronic Devices ◽  
Deposition Process ◽  
Shielding Effectiveness ◽  
Emi Shielding ◽  
Emi Shielding Effectiveness ◽  
X Band ◽  
Wearable Electronic Devices ◽  
Emi Se

AbstractLightweight, flexibility, and low thickness are urgent requirements for next-generation high-performance electromagnetic interference (EMI) shielding materials for catering to the demand for smart and wearable electronic devices. Although several efforts have focused on constructing porous and flexible conductive films or aerogels, few studies have achieved a balance in terms of density, thickness, flexibility, and EMI shielding effectiveness (SE). Herein, an ultrathin, lightweight, and flexible carbon nanotube (CNT) buckypaper enhanced using MXenes (Ti3C2Tx) for high-performance EMI shielding is synthesized through a facile electrophoretic deposition process. The obtained Ti3C2Tx@CNT hybrid buckypaper exhibits an outstanding EMI SE of 60.5 dB in the X-band at 100 μm. The hybrid buckypaper with an MXene content of 49.4 wt% exhibits an EMI SE of 50.4 dB in the X-band with a thickness of only 15 μm, which is 105% higher than that of pristine CNT buckypaper. Furthermore, an average specific SE value of 5.7 × 104 dB cm2 g−1 is exhibited in the 5-μm hybrid buckypaper. Thus, this assembly process proves promising for the construction of ultrathin, flexible, and high-performance EMI shielding films for application in electronic devices and wireless communications.

Analysis of vibration response and machining quality of hybrid robot based UD-CFRP trimming

2021 ◽  
pp. 095440542098609
Author(s):  
Yan Zhang ◽  
Hao Li ◽  
Xuda Qin ◽  
Jie liu ◽  
Zhuojie Hou
Keyword(s):  
High Performance ◽  
Vibration Response ◽  
Industrial Robots ◽  
Force Characteristic ◽  
Surface Waviness ◽  
Machined Surface ◽  
Machining Quality ◽  
3D Surface Roughness ◽  
Machined Surface Quality ◽  
Vibration Responses

To fulfill the demands of higher precision, better quality, and more flexibility, the usage of high-performance industrial robots is rapidly increased in aerospace industry. Considering the anisotropic and inhomogeneous characteristics of composite materials, this study focuses mainly on dynamic response investigation of a newly designed hybrid robot (named as TriMule) in CFRP trimming process and its influence on the machined quality. First, combined with the cutting force characteristic, the vibration responses of tool center point (TCP) under the dynamic excitation were obtained. The influences of robotic TCP vibration on machined surface quality with different fiber orientations, including surface waviness, cavity, 3D surface roughness, and depth of affected zone, are first studied by comparing hybrid robot and machine tool. From experiment results, it can be concluded the proposed TCP vibration response model has sufficient prediction accuracy. Meanwhile, it is found that larger robotic vibration response is accompanied by higher surface waviness, bigger surface cavity, and greater affected zone. Results also showed that the fiber orientation and milling style are two essential factors that affect robot vibration and machining quality during CFRP trimming.

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