Development of Electron Beam Cross-Linked PDMS/PTFEM Composites with Low Coefficient of Friction and High Elastic Modulus

In this study, we present the results of Young’s modulus and coefficient of friction (COF) of Ti–Ta surface alloys formed by electron-beam surface alloying by a scanning electron beam. Ta films were deposited on the top of Ti substrates, and the specimens were then electron-beam surface alloyed, where the beam power was varied from 750 to 1750 W. The structure of the samples was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). Young’s modulus was studied by a nanoindentation test. The coefficient of friction was studied by a micromechanical wear experiment. It was found that at 750 W, the Ta film remained undissolved on the top of the Ti, and no alloyed zone was observed. By an increase in the beam power to 1250 and 1750 W, a distinguished alloyed zone is formed, where it is much thicker in the case of 1750 W. The structure of the obtained surface alloys is in the form of double-phase α’and β. In both surface alloys formed by a beam power of 1250 and 1750 W, respectively, Young’s modulus decreases about two times due to different reasons: in the case of alloying by 1250 W, the observed drop is attributed to the larger amount of the β phase, while at 1750 W is it due to the weaker binding forces between the atoms. The results obtained for the COF show that the formation of the Ti–Ta surface alloy on the top of Ti substrate leads to a decrease in the coefficient of friction, where the effect is more pronounced in the case of the formation of Ti–Ta surface alloys by a beam power of 1250 W.

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Design and preparation of high elastic modulus self-compacting concrete for pre-stressed mass concrete structures

Journal of Wuhan University of Technology-Mater Sci Ed ◽

10.1007/s11595-016-1411-y ◽

2016 ◽

Vol 31 (3) ◽

pp. 563-573 ◽

Cited By ~ 4

Author(s):

Wen Zhu ◽

Yang Chen ◽

Fangxian Li ◽

Tongsheng Zhang ◽

Jie Hu ◽

...

Keyword(s):

Elastic Modulus ◽

Concrete Structures ◽

Mass Concrete ◽

Self Compacting Concrete ◽

High Elastic Modulus

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Materials characterization and effect of purity and ion implantation on the friction and wear of sublimed fullerene films

Journal of Materials Research ◽

10.1557/jmr.1994.2823 ◽

1994 ◽

Vol 9 (11) ◽

pp. 2823-2838 ◽

Cited By ~ 42

Author(s):

B.K. Gupta ◽

Bharat Bhushan ◽

C. Capp ◽

J.V. Coe

Keyword(s):

Fourier Transform ◽

Elastic Modulus ◽

Ion Implantation ◽

Coefficient Of Friction ◽

Friction And Wear ◽

Steel Ball ◽

Scanning Tunneling ◽

High Dose ◽

Wear Life ◽

Plastic Deformation Behavior

In previous studies, sublimed C60-rich fullerene films on silicon, when slid against a 52100 steel ball under dry conditions, have exhibited low coefficient of friction (∼0.12). Films with different purities can be produced by sublimation at different substrate temperatures. In this paper, effects of purity of fullerene films and ion implantation of the films with Ar ions on the friction and wear properties of sublimed fullerene films are reported. C60-rich films (called here films with high purity) exhibit low macroscale friction. An increased amount of C70 and impurities in the fullerene film determined using Raman and Fourier transform infrared (FTIR), increases its coefficient of friction. Microscale friction measurements using friction force microscopy also exhibited similar trends. Low coefficient of friction of sublimed C60-rich films on silicon is probably due to the formation of a tenacious transfer film of C60 molecules on the mating 52100 steel ball surface. Based on scanning tunneling microscopy (STM), transmission electron microscopy (TEM), and high resolution TEM (HRTEM), we found that fullerene films primarily consisted of C60 molecules in a fcc lattice structure. Nanoindenter was used to measure hardness and elastic modulus of the as-deposited films. Ion-implantation with 1 × 1016 Ar+ cm−2 reduced macroscale friction down to about 0.10 from 0.12 with an increase in wear life by a factor of 4; however, doses of 5 × 1016 ions cm−2 gave three times higher friction and poorer wear life; higher doses disintegrated the C60 molecules. Based on STM, TEM, Raman, FTIR, and laser desorption Fourier-transform ion cyclotron resonance mass spectrometer (LD/FT/ICR) studies, we found that the ion implantation with a dose of 1 × 1016 Ar+ cm−2 resulted in smoothening of the fullerene film surface probably by compacting clusters, but without disintegrating the C60 molecules. However, a high dose of 5 × 1016 Ar+ cm−2 damaged the C60 molecules, converting it to an amorphous carbon. Nanoindentation studies show that ion implantation with a dose of 1 × 1016 Ar+ cm−2 resulted in an increase in the hardness from about 1.2 to 4.0 GPa and in elastic modulus from about 70 to 75 GPa and modified the elastic-plastic deformation behavior.

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Microstructure and mechanical properties of as cast titanium alloys with high elastic modulus

Materials Research Innovations ◽

10.1179/1432891714z.000000000679 ◽

2014 ◽

Vol 18 (sup4) ◽

pp. S4-212-S4-214

Author(s):

Y. L. Qi ◽

L. Y. Zeng ◽

Z. M. Hou ◽

Q. Hong ◽

S. B. Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Elastic Modulus ◽

Titanium Alloys ◽

High Elastic Modulus ◽

Microstructure And Mechanical Properties

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Fiber-reinforced-superconductors with high-elastic modulus and low thermal prestrain on Nb/sub 3/Sn layers for high-field pulsed magnet

IEEE Transactions on Magnetics ◽

10.1109/20.305700 ◽

1994 ◽

Vol 30 (4) ◽

pp. 2164-2167 ◽

Cited By ~ 3

Author(s):

K. Arai ◽

H. Tateishi ◽

M. Umeda ◽

K. Agatsuma ◽

S. Takizawa

Keyword(s):

Elastic Modulus ◽

High Field ◽

Fiber Reinforced ◽

Pulsed Magnet ◽

High Elastic Modulus

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Time-dependent nanoindentation behavior of high elastic modulus dental resin composites

Journal of Materials Research ◽

10.1557/jmr.2010.0070 ◽

2010 ◽

Vol 25 (3) ◽

pp. 529-536 ◽

Cited By ~ 4

Author(s):

Yijun Wang ◽

Isabel K. Lloyd

Keyword(s):

Elastic Modulus ◽

Volume Fraction ◽

Resin Composite ◽

Acrylic Resin ◽

Resin Matrix ◽

Resin Composites ◽

Dental Resin ◽

Elastic Plastic ◽

High Elastic Modulus ◽

Continuous Stiffness Measurement

Nanoindentation and the viscous-elastic–plastic (VEP) model developed by Oyen and Cook for lightly filled thermoplastic polymer composites were used to characterize the elastic modulus, hardness, and viscoelastic response of a new high elastic modulus dental resin composite. The VEP model was used because loading rate studies indicated a viscous component in the loading/unloading response of our highly filled, thermosetting acrylic resin composites. Increasing the volume fraction of our high modulus filler increased the elastic modulus and hardness and decreased the viscous response in our composites. Coupling the filler and resin matrix with a commercial coupling agent like Metaltite or MPTMS (3-methacryloxypropyltrimethoxysilane) that ionically bonds to the filler and covalently bonds to the matrix decreases the viscous response and increases the hardness of the composite. The coupling agents did not affect the elastic modulus. The ability of the VEP model to predict load–displacement trajectories and the correlation of the elastic modulus and hardness values determined from the VEP model with those from the direct continuous stiffness measurement mode nanoindentation measurements indicate that the VEP model can be extended to highly filled, thermosetting systems. This is valuable since the potential to predict elastic, plastic, and viscous contributions to behavior should be valuable in the design and understanding of future highly filled resin composite systems.

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