Effect of Microstructure in Metal Reinforced Composite CVD Diamond Films on Mechanical Properties

1995 ◽  
Vol 383 ◽  
Author(s):  
J. W. Hoehn ◽  
D. F. Bahr ◽  
J. Heberlein ◽  
E. Pfender ◽  
W. W. Gerberich
Keyword(s):  
Mechanical Properties ◽  
Diamond Films ◽  
Composite Layer ◽  
Compositional Analysis ◽  
Cvd Diamond ◽  
Carbon Layer ◽  
X Ray ◽  
Diamond Crystals ◽  
Composition And Structure ◽  
Interfacial Composition

ABSTRACTComparison of behavior observed during deadhesion of CVD diamond films and compositional analysis of their microstructure allows a correlation between microstructure and mechanical behavior to be made. Diamond films were grown in a DC Triple Torch Reactor using a mixture of methane and hydrogen on molybdenum substrates. To address the issue of voids at the interface, a metal binder was electroplated after the nucleation of individual diamond crystals on the substrates. The films were completed by growing a layer of diamond upon the composite layer. Interfacial composition and structure of the films are characterized by a x-ray, Auger, and Raman spectroscopy. A carbide may act to enhance the adhesion via chemical bonding between the substrate and film. Diffusion of the binder into the substrate and film is also important for mechanical properties and is confirmed by x-ray mapping. It is suggested that a diamond like carbon layer acts to enhance the adhesion of the film to the substrate.

scholarly journals Enhancement of the Mechanical Properties in Al–Si–Cu–Fe–Mg Alloys with Various Processing Parameters

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2150 ◽  
Author(s):  
Su-Seong Ahn ◽  
Sharief Pathan ◽  
Jar-Myung Koo ◽  
Chang-Hyun Baeg ◽  
Chan-Uk Jeong ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Electron Microscope ◽  
Silicon Content ◽  
Compositional Analysis ◽  
Processing Parameters ◽  
Silicon Phase ◽  
X Ray ◽  
Primary Si ◽  
Transmission Electron ◽  
Eutectic Si

In this research, various processing conditions were implemented to enhance the mechanical properties of Al-Si alloys. The silicon content was varied from hypoeutectic (Si-10 wt.%) to eutectic (Si-12.6 wt.%) and hypereutectic (Si-14 wt.%) for the preparation of Al-XSi-3Cu-0.5Fe-0.6 Mg (X = 10–14%) alloys using die casting. Subsequently, these alloys were hot-extruded with an optimum extrusion ratio (17:1) at 400 °C to match the output extruded bar to the compressor size. An analysis of the microstructural features along with a chemical compositional analysis were carried out using scanning electron microscope along with energy dispersive X-ray spectroscopy and transmission electron microscope. The SEM micrographs of the extruded samples displayed cracks in primary Si, and the intermetallic (β-Al5FeSi) phase was fragmented accordingly. In addition, the silicon phase was homogenously distributed, and the size remained constant. The mechanical properties of the extruded samples were enhanced by the increase of silicon content, and consequently the ductility decreased. By implementing proper T6 heat treatment parameters, coherent Al2Cu phases were formed in the Al matrix, and the Si phase was gradually increased along with the silicon content. Therefore, high tensile strength was achieved, reaching values for the Al-XSi-3Cu-0.5Fe-0.6Mg (X = 10–14%) alloys of 366 MPa, 388 MPa, and 420 MPa, respectively.

scholarly journals Mechanical Properties of Boron-Doped CVD Diamond Films

2010 ◽  
Vol 61 (3) ◽  
pp. 274-278 ◽  
Author(s):  
Sadao TAKEUCHI ◽  
Takashi MURAISHI
Keyword(s):  
Mechanical Properties ◽  
Diamond Films ◽  
Cvd Diamond ◽  
Boron Doped

Interfacial Composition and Structure in Pt/Ni and Pt/Nb Multilayer Films

1990 ◽  
Vol 187 ◽  
Author(s):  
J.A. Bain ◽  
B.M. Clemens ◽  
S. Brennan
Keyword(s):  
Lattice Spacing ◽  
Grazing Incidence ◽  
Multilayer Films ◽  
Interfacial Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Composition And Structure ◽  
Interfacial Composition ◽  
Alloying Effects ◽  
Coherent Interfaces

AbstractThe interfacial structure of Pt/Nb and Pt/Ni sputtered multilayer films was studied using x-ray diffraction in symmetric, asymmetric, and grazing incidence modes. The grazing incidence and asymmetric diffraction were used to distinguish alloying effects on the lattice spacing from strain in the films. This strain was shown to be consistent with semi-coherent interfaces in the Pt/Ni but not in the Pt/Nb in which another strain generating mechanism dominates.

Local order in CVD diamond films : Comparative Raman, x-ray-diffraction, and x-ray-absorption near-edge studies

1998 ◽  
Vol 57 (22) ◽  
pp. 14123-14132 ◽  
Author(s):  
L. Fayette ◽  
B. Marcus ◽  
M. Mermoux ◽  
G. Tourillon ◽  
K. Laffon ◽  
...  
Keyword(s):  
Diamond Films ◽  
Cvd Diamond ◽  
Local Order ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Absorption

Platelet Adhesion Study and Characteristic of Hydrogenated Carbon Films Synthesized by PIII-D

2005 ◽  
Vol 288-289 ◽  
pp. 323-326 ◽  
Author(s):  
Feng Wen ◽  
Nan Huang ◽  
H. Sun ◽  
Ping Yang ◽  
Jin Wang
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Raman Spectra ◽  
Room Temperature ◽  
Platelet Adhesion ◽  
Carbon Films ◽  
Photoelectron Spectra ◽  
X Ray ◽  
Composition And Structure ◽  
Amorphous Hydrogenated Carbon

Amorphous hydrogenated carbon (a-C:H) thin films were deposited on silicon wafers and Ti6Al4V substrate using plasma ion immersion implantation and deposition (PIII-D) at room temperature (R.T.). The composition and structure of a-C:H films were employed by X-ray photoelectron spectra (XPS) and Raman spectra. Nano-indenter tests measured the hardness of the films. In addition, wettability and bloodcompatibility were investigated. In this paper, the effects of hydrogen content on structure, mechanical properties, surface wettability and haemocompatibility were discussed.

X-ray photoelectron spectroscopy studies of CVD diamond films

2002 ◽  
Vol 34 (1) ◽  
pp. 703-707 ◽  
Author(s):  
Y. Fan ◽  
A. G. Fitzgerald ◽  
P. John ◽  
C. E Troupe ◽  
J. I. B. Wilson
Keyword(s):  
Photoelectron Spectroscopy ◽  
Diamond Films ◽  
Cvd Diamond ◽  
X Ray ◽  
Spectroscopy Studies

Growth of (100) oriented diamond thin films on ball structure diamond-like particles

1992 ◽  
Vol 7 (7) ◽  
pp. 1606-1609 ◽  
Author(s):  
Lee Chow ◽  
Alan Horner ◽  
Hooman Sakouri ◽  
Bahram Roughani ◽  
Swaminatha Sundaram
Keyword(s):  
Thin Films ◽  
Substrate Temperature ◽  
Diamond Films ◽  
Cvd Diamond ◽  
X Ray ◽  
Oriented Films ◽  
Diamond Thin Films

The morphology of typical CVD diamond thin films has been shown to be controlled by the concentration of methane during deposition. For example, for CH4 concentrations c < 0.4% the (111) faces dominate, while at 0.4% < c < 1.2% (100) faces dominate. Here we showed that the (100) oriented diamond films can be grown on top of the microcrystalline ball-like particles under suitable conditions. These (100) oriented diamond films are grown under the condition of 1.5% methane in hydrogen, substrate temperature of 680 °C–750 °C, and pressure of 30–80 Torr. The bombardment of the diamond thin films by ions in the plasma is believed to be an important factor for the formation of (100) oriented films on top of the ball-like particles. SEM, Raman, and x-ray techniques were used to characterize the deposited (100) oriented diamond thin films.

Grain Impingement and Intrinsic Stresses in CVD Diamond

1997 ◽  
Vol 505 ◽  
Author(s):  
S. Nijhawan ◽  
J. Rankin ◽  
B. L Walden ◽  
B. W. Sheldon
Keyword(s):  
Tensile Strain ◽  
Diamond Films ◽  
Cvd Diamond ◽  
Intermediate Annealing ◽  
X Ray Diffraction ◽  
Entire Sample ◽  
X Ray ◽  
Pole Figures ◽  
Annealing Step ◽  
Film Microstructure

ABSTRACTIntrinsic stresses in polycrystalline CVD diamond films have been related to restructuring at grain boundaries. It is speculated that reducing the interfacial energy induces an elastic tensile strain. There appears to be a correlation between the evolution of macroscopic stresses in the entire sample and localized, non-homogeneous stresses in the microstructure based on Raman Spectroscopy and x-ray diffraction pole figures. A multistep processing sequence developed previously can help reduce these stresses substantially, by using an intermediate annealing step when the diamond grains are partially coalesced. Our results suggest that small changes in the film microstructure due to annealing can reduce both homogeneous and non-homogeneous stresses.

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

1995 ◽  
Vol 383 ◽  
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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