Tribological Properties of Cu Based Friction Composites with In Situ Synthesized TiC Filler

The Cu based friction composites using graphite as solid lubricant with different weight rations of Ti, i.e. 8 wt.%, 12 wt.%, 16 wt.%, 20 wt.%, were sintered by powder metallurgy (P/M) method. The structure of the composites was characterized by X-ray diffraction (XRD) and the tribological properties was studied on block-on-ring tester. XRD results verified presence of TiC phase which was in-situ synthesized through reaction of Ti and graphite in the composites, and the content of TiC was increased with the increased Ti content. The in-situ synthesized TiC phase which was fine and distributed uniformly improved tribological properties of Cu based friction composites significantly. The hardness, wear rates and friction coefficient of composites were increased with increasing amount of in-situ synthesized TiC.

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Preparation and Tribological Behavior of Self-Lubrication Composites Ni-W-Cr-Fe-Cu-MoS2-Graphite at Elevated Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.668.3 ◽

2013 ◽

Vol 668 ◽

pp. 3-8 ◽

Cited By ~ 1

Author(s):

Jian Rong Sun ◽

Chang Sheng Li ◽

Hua Tang ◽

Zhi Cheng Guo ◽

Jin Ying Zi Liu

Keyword(s):

Tensile Strength ◽

Elevated Temperature ◽

Powder Metallurgy ◽

Friction Coefficient ◽

Tribological Properties ◽

Room Temperature ◽

Tribological Behavior ◽

Strengthening Effect ◽

Wear Rates ◽

Increasing Temperature

The composites of Ni-W-Cr-Fe-Cu-MoS2-Graphite with nano-MoS2 were prepared by powder metallurgy. Its tribological properties were investigated using the UTM-2 Nano+Micro Tribometer from room temperature to 600°C. The effects of amount of MoS2 and Ni-W-Cr prealloy powder, load, and temperature on the tribological properties were investigated and discussed. The results indicated that the addition of 43~45wt.% Ni-W-Cr prealloy powder had a strengthening effect on the hardness, anti-press and tensile strength. The tensile strength of the composite decreases with the addition of Nano-MoS2 and graphite, and the friction coefficient decrease with increase of the additives over the wide temperature range of 25°C∼600°C. The friction coefficients and wear rates of the composites reach the optimization value at 2.5wt.% MoS2,While its wear rates increase with the increasing temperature and load.

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Studying the Microstructure of Al-Ti Alloy Prepared by Powder Metallurgy using Three Different Percentages of Ti

Journal of Engineering ◽

10.31026/j.eng.2020.06.11 ◽

2020 ◽

Vol 26 (6) ◽

pp. 132-139

Author(s):

Sahib Mohammed Mahdi ◽

Nadia Ghadhanfer Hikmat ◽

Dalmn Yaseen Taha

Keyword(s):

Electron Microscope ◽

Powder Metallurgy ◽

Optical Microscope ◽

Ti Alloy ◽

Micro Hardness ◽

X Ray Diffraction ◽

X Ray ◽

Alloy Properties ◽

Ti Content ◽

Scanning Electron

The effect of different Ti additions on the microstructure of Al-Ti alloy prepared by powder metallurgy was investigated. A certain amount of Ti (10wt%, 15wt%, and 20wt%) were added to aluminium and the tests like microhardness, density, scanning electron microscope (SEM), optical microscope (OM) and X-Ray Diffraction (XRD) were conducted to determine the influence of different Ti additives on the Al-Ti alloy properties and microstructure. The results show that the grains of α-Al changed from large grains to roughly spherical and then to small rounded grains with increasing Ti content, the micro-hardness of the alloy increases with increasing Ti, and XRD results confirm the formation of TiAl3 intermetallic compound during sintering.

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TRIBOLOGICAL PROPERTIES OF AG/BSCCO SELF-LUBRICATING COMPOSITES

International Journal of Modern Physics B ◽

10.1142/s021797921006543x ◽

2010 ◽

Vol 24 (15n16) ◽

pp. 2664-2669

Author(s):

LIRONG DONG ◽

CHANGSHENG LI ◽

TANG HUA

Keyword(s):

Stainless Steel ◽

Friction Coefficient ◽

Tribological Properties ◽

Test Time ◽

Powder Metallurgy Method ◽

Superconducting Transition ◽

Test Results ◽

X Ray Diffraction ◽

X Ray ◽

Electronic Microscope

The superconductors Bi 2 Sr 2 CaCu 2 O x ( Bi 2212 ) and Ag / Bi 2212 composites samples were prepared by the powder metallurgy method. The frictional behaviors of Bi 2212 pins in contact with stainless steel plate were examined from -196 to 20°C on friction and wear tester. When the temperature was lower than the superconducting transition temperature, the friction coefficient of Bi 2212 dropped sharply, and it kept 0.11 with increase of the test time. The microstructure and morphology of Ag / Bi 2212 composites were investigated by means of X-ray diffraction (XRD), transmission electronic microscope (TEM) and high resolution transmission electronic microscope (HRTEM). The elemental compositions of the worn surfaces of Ag / Bi 2212 composites were determined by using energy dispersive X-ray analysis (EDXA). The results showed that the superconducting structure of Bi 2212 was not changed and Ag was distributed in the Bi 2212 matrix. Ag doping improved the toughness of oxide ceramics Bi 2212. The friction test results of Ag / Bi 2212 composites showed the tribological properties were improved at room temperature. The friction coefficient of 10% Ag / Bi 2212 against stainless steel showed a lower value (0.2) and the wear rate of 15% Ag / Bi 2212 was minimum (9.5×10-5 mm3·(N·m)-1 ). The lubrication of soft metallic film and load of hard matrix were the mechanism of decreased friction and anti-wear of Ag / Bi 2212 composites.

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Study on Properties of Cupriferous and Boracic Iron Based Sintered Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.756-759.80 ◽

2013 ◽

Vol 756-759 ◽

pp. 80-84

Author(s):

Ming Hua Jiao ◽

Bing Chao Wan ◽

Bai Wan Su ◽

Shao Bo Ma ◽

Yan Guo Yin

Keyword(s):

Powder Metallurgy ◽

Synergistic Effect ◽

Tribological Properties ◽

Friction And Wear ◽

Sinter Process ◽

X Ray Diffraction ◽

X Ray ◽

Iron Based ◽

Self Lubricating Composites

Pre-configured powders were mixed uniformly through bonding granulation method. The boracic iron based self-lubricating composites with copper of different mass were prepared by the powder metallurgy press-sinter process. The tribological properties under different conditions of load were investigated on HDM20 end-face tribometer. The composite structure, the wear mechanism which copper affect the friction and wear behaviors of boracic iron based composites were analyzed by using X-ray diffraction, EDS and metallographic microscope. The results show that elementary copper which forming alloy phase could strengthen the combination of each phase in composites, playing the role of binder, improve the tribological properties. The synergistic effect between the phases combination, hardness and strength of Cu-20w composite were observably, which lead to the excellent tribological properties synthetically.

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Microstructure, Mechanical and Tribological Properties of Reactive Magnetron Sputtered Titanium Carbide Coatings

ASME/STLE 2007 International Joint Tribology Conference, Parts A and B ◽

10.1115/ijtc2007-44457 ◽

2007 ◽

Author(s):

Kyriaki Polychronopoulou ◽

Claus Rebholz ◽

Nicholaos G. Demas ◽

Andreas A. Polycarpou ◽

Lefki Theodorou ◽

...

Keyword(s):

Chemical Composition ◽

Carbon Content ◽

Tribological Properties ◽

Photoelectron Spectroscopy ◽

Reactive Magnetron ◽

X Ray Diffraction ◽

X Ray ◽

Wear Rates ◽

Mechanical And Tribological Properties ◽

Carbide Coatings

This study describes the correlation between the microstructure, mechanical and tribological properties of Ti1−xCx coatings (with x being in the range of 0–0.5), deposited by reactive magnetron sputtering from a Ti target in Ar/C2H2 mixtures at ∼200 °C. The mechanical and tribological properties were found to strongly depend on the chemical composition and the microstructure present. Very dense structures and highest hardness and elastic modulus, combined with low wear rates, were observed for films with chemical composition close to TiC. X-ray diffraction (XRD) studies showed that the coating deposited at high C2H2 flow rates composed of randomly oriented TiC crystallites. Morphological investigations by scanning electron microscopy (SEM) indicate that the morphology is strongly dependent on the carbon content of the coating. Coatings composition and bonding environment was investigated using X-ray photoelectron spectroscopy (XPS). Both the mechanical properties and tribological performance of the coatings were found to be dependent on carbon content.

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Improvement of the Tribological Properties of Alumina Coatings by Zirconia Addition

Coatings ◽

10.3390/coatings11080991 ◽

2021 ◽

Vol 11 (8) ◽

pp. 991

Author(s):

Jacob Shiby Mathew ◽

Liutauras Marcinauskas ◽

Mitjan Kalin ◽

Romualdas Kėželis ◽

Žydrūnas Kavaliauskas ◽

...

Keyword(s):

Tribological Properties ◽

Atmospheric Plasma ◽

X Ray Diffraction ◽

Alumina Coatings ◽

X Ray ◽

Wear Rates ◽

Arc Current ◽

Α Al2o3 ◽

Sprayed Coatings ◽

Zirconia Addition

Al2O3 and Al2O3-ZrO2 coatings were deposited on stainless steel using atmospheric plasma spraying. The influence of arc current and zirconia addition on the surface morphology of the coating, phase composition and tribological properties under dry sliding conditions were investigated. The addition of zirconia reduced the surface roughness of the coatings. The X-ray diffraction measurements indicated that the Al2O3 coatings were composed of β-Al2O3, α-Al2O3, and γ-Al2O3 phases. The addition of zirconia led to the formation of tetragonal and monoclinic phases of zirconia in the as-sprayed coatings. The friction coefficients of Al2O3 and Al2O3-ZrO2 coatings were similar and varied in the range of 0.72–0.75. The specific wear rates of the as-sprayed coatings were reduced with the increase of arc current. It was obtained that the wear rates of the Al2O3-ZrO2 coatings were at least three times lower compared to Al2O3 coatings.

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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