Production, Characterization, and Wear Behaviour of Plasma Jet CVD Diamond Films on Hard Metal Cutting Tools

Silicon Nitride is largely used as the base material to manufacture cutting tools. Due to its low thermal expansion coefficient it is ideal candidate for CVD diamond deposition. In this work, we functionalized the surface of silicon nitride inserts (Si3N4) with a polymer (PDDA Poly (diallyldimethylamonium chloride - Mw 40000)) to promote seeding with nanodiamond particles. The seeding was performed in water slurry containing 4 nm diamond particles dispersed by PSS Poly (sodium4-styrenesulfonate) polymer. CVD diamond films, with high nucleation density, were deposited in a hot filament reactor. Film morphology was characterized by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). Diamond film quality was determined by Raman Spectroscopy. CVD diamond film adherence was evaluated using Rockwell C indentation.

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High Current Extended DC Arc Plasma CVD for Mass Production of Diamond Film Coated Hard Metal Cutting Tools

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.211-212.766 ◽

2011 ◽

Vol 211-212 ◽

pp. 766-769 ◽

Cited By ~ 2

Author(s):

Fan Xiu Lu ◽

Yong Ping Lv ◽

Li Fu Hei ◽

Wei Zhong Tang ◽

Jian Hua Song

Keyword(s):

Diamond Film ◽

Mass Production ◽

Metal Cutting ◽

High Efficiency ◽

Cutting Tools ◽

Hard Metal ◽

High Current ◽

Plasma Cvd ◽

Dry Cutting ◽

Dc Arc

Diamond film coated hard metal cutting tools are indispensible for high efficiency machining of materials which are difficult to cut by ordinary tools, and are successfully used in the dry cutting of high silicon content Al-Si cast alloys, graphite, carbon reinforced composite (CRFC) and metal matrix composite (MMC) , ceramics, and many other materials. In the present presentation, a novel process of High Current Extended DC Arc (HCEDCA) plasma CVD for mass production of diamond film coated hard metal cutting tools is presented. Besides, a novel process for the pretreatment of the hard metal cutting tool substrate, which involves the idea of “surface engineering” consisting of boronizing and alkaline and acidic etching is also discussed, by which the adhesion of the diamond film coating to the hard metal substrate can be greatly enhanced. Highly adherent and uniform diamond film coatings are successfully obtained. Diamond film coated WC-6wt%Co indexable tool bits, drills, endmill samples have been produced and been shown having excellent cutting performance by field cutting tests in dry cutting of Al-12%Si cast alloy and Al-15% SiC MMC materials.

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Adhesion Evaluation of CVD Diamond Films and Metal Reinforced Composite Diamond Films

MRS Proceedings ◽

10.1557/proc-383-209 ◽

1995 ◽

Vol 383 ◽

Cited By ~ 1

Author(s):

D. F. Bahr ◽

J..C. Nelson ◽

D. Zhuang ◽

E. Pfender ◽

J. Heberlein ◽

...

Keyword(s):

Composite Films ◽

Cutting Tools ◽

Diamond Films ◽

Composite Layer ◽

Cvd Diamond ◽

Single Step ◽

Diamond Growth ◽

Metal Binder ◽

Tension And Compression ◽

Bend Tests

ABSTRACTPoor adhesion of diamond films limits the use of CVD diamond films as coatings for cutting tools. The adhesion of these films is limited by stresses in the film caused by thermal expansion mismatch between the substrate and the film and by voids present at the interface due to the morphology of the crystal growth. A three step process of making diamond composite films has been developed, involving nucleation of individual diamonds on the substrate, electroplating a metal binder in the voids between the crystals, and lastly growing a complete film over the composite layer. The metal binder acts both to fill the voids at the interface and to absorb energy during fracture processes at the interface. Diamond growth was performed in a DC Triple Torch reactor using a mixture of methane and hydrogen with a molybdenum substrate. Measurements to determine the amount of improvement of the film adhesion have been performed. These tests include indentations using conventional hardness testing equipment and four point bend tests with the film in tension and compression. A correlation is shown between the plastic zone of the substrate and the area of the film which delaminated during indentation. Bend tests with the film in tension did not delaminate the film, instead the film underwent intergranular fracture. Bend tests in compression act similarly to pile up around an indentation, and cause film delamination. Residual stress measurements in the single step film show a compressive stress of 650 MPa.

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Non-destructive characterization of CVD diamond films on cemented carbide cutting tools

Diamond and Related Materials ◽

10.1016/s0925-9635(97)00172-6 ◽

1998 ◽

Vol 7 (2-5) ◽

pp. 589-596 ◽

Cited By ~ 10

Author(s):

D. Schneider ◽

B. Schultrich ◽

P. Burck ◽

H.-J. Scheibe ◽

G. Jörgensen ◽

...

Keyword(s):

Cutting Tools ◽

Diamond Films ◽

Cvd Diamond ◽

Cemented Carbide ◽

Non Destructive ◽

Non Destructive Characterization

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Paris Salon showcases hard metal cutting tools

Metal Powder Report ◽

10.1016/s0026-0657(13)70123-1 ◽

2013 ◽

Vol 68 (4) ◽

pp. 22-23

Author(s):

Ken Brookes

Keyword(s):

Metal Cutting ◽

Cutting Tools ◽

Hard Metal ◽

Paris Salon

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A new quick-stop device to study the chip formation mechanism in metal cutting: Computational and experimental investigation

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211034210 ◽

2021 ◽

pp. 095440622110342

Author(s):

Mohamed Baccar Mhamdi ◽

Wajdi Rajhi ◽

Mohamed Boujelbene ◽

Sahbi Ben Salem ◽

Sonia Ezeddini ◽

...

Keyword(s):

Chip Formation ◽

Metal Cutting ◽

Cutting Tools ◽

Cutting Parameters ◽

Hard Metal ◽

Formation Mechanisms ◽

Machining Parameters ◽

Chip Formation Mechanism ◽

Aisi D2 ◽

Stop Test

Understanding the chip formation mechanisms during machining is an important factor to facilitate the choice of cutting tools and machining parameters. Despite the appearance of new sophisticated methods and advanced equipment, the technique so called quick-Stop Test (QST) remains efficient, less costly, and easier to apply in the investigation of chip formation in cutting process. In present paper a new Quick-Stop Device QSD is designed, numerically simulated, implemented, and tested. The reformed QST technique uses a QSD device which operates on the modified Charpy pendulum. Accordingly, design of new QSD is presented and deeply described, and 2D FE modeling of the new QST, including the application of the appropriate boundary conditions, has been carried out. Moreover, chip formation and morphology for different cutting conditions have been effectively simulated. Subsequently, quick stop cutting operations including metal cutting tests of high alloyed tool steel (AISI D2) using fabricated new QSD are performed. Preliminary results of quick-stop experiment from current investigation prove the effectiveness of the new designed QSD in matter of rigidity, safety, and absence of vibration, while providing a fast set up time and allowing extremely short workpiece-cutting tool separation time and guarantee the generation of chip with its root. The photomicrographs of chip root samples gathered from hard metal cutting experiments including various cutting speeds machining conditions, enables clear observation of segmented chip formation mechanisms, thereby, highly promising the new designed QSD for the purpose of investigation of the different cutting parameters influencing the chip formation and morphology.

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Study and Development of a Multilayered Coating to Improve Hard Metal Cutting Tools Performances

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.1656 ◽

2018 ◽

Vol 941 ◽

pp. 1656-1661

Author(s):

Federico Simone Gobber ◽

Mario Rosso

Keyword(s):

Metal Cutting ◽

Multilayer Coating ◽

Cutting Tools ◽

Hard Metal ◽

Point Of View ◽

Thin Layers ◽

Mechanical Working ◽

Heat Resistant Alloy ◽

Experimental Cutting ◽

The Difference

The use of coated hard metal is spread in all fields of mechanical working, both forming and machining. Different hard metals are used based on their mechanical characteristic that strongly depends on composition and grain size. Substrates such as HSS and WC – Co are typically coated with PVD thin layers in applications such as metalworking and cutting; thus lot of efforts are put in researching this specific field. Coating composition, and coating architecture are paramount topics in the subsject of surface anti – wear thin films. The focus of this study is to analyze the difference between two AlTiN coatings, a monolayer and a multilayer with gradient composition, from the point of view of microstructure and adhesion. Experimental cutting tests were done to characterize the behavior of the coating in face milling of AISI 660 heat resistant alloy: varying cutting speeds from 15 to 40 m/min it was finally assessed that a multilayer coating can give higher tool life with respect to a monolayer coating of the same composition.

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Development of Ultra Fine Crystalline Diamond Film and Some Applications

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.461 ◽

2004 ◽

Vol 449-452 ◽

pp. 461-464

Author(s):

Yoshihiko Murakami ◽

H. Liu ◽

H. Hanyu

Keyword(s):

Surface Finish ◽

Diamond Film ◽

Copper Alloys ◽

Cutting Tools ◽

Diamond Films ◽

Cvd Diamond ◽

Fine Surface ◽

Edm Electrodes ◽

End Mills ◽

Cvd Diamond Film

We would like to report on the development of our new ultra fine crystalline CVD diamond film and some applications. CVD Diamond films have good wear resistance, but the crystal size is too large. Therefore, in case of application of diamond films for cutting tools, we cannot get fine surface finish on work materials. Recently we succeed in production ultra fine crystalline CVD diamond film and various cutting tools as taps, drills and end mills. Aluminum alloys have lately been consumed more than ever in airplanes and automobiles for the purpose of decreasing the weight of structural materials.Copper alloys are used for the electrode of electric discharge machines (EDM) recently. EDM electrodes are required fine surface finish because the surface quality of mold depends on accuracy of EDM electrodes. Soft materials such as aluminum and copper alloys have high viscosity and additionally activity. So during cutting aluminum and copper alloys we have sometimes adhesion between cutting tools and work pieces. Diamond film on tools is able to improve the reactivity to aluminum and copper alloys. But up to now the diamond film has a lot of course crystal and tend to supply rough surface finish on work pieces. We developed ultra fine crystalline diamond film on end mills by plasma chemical vapor deposition (CVD) method. Now our aircraft, automotive and molding customers can get smooth surface finish of work pieces.Keeping ISO14001, we recommend oil free cutting with ultra fine crystalline diamond coated cutting tools. Here I introduce background of the development and cutting examples with new fine diamond coated end mills.

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