scholarly journals Tribological and Mechanical Behavior of Graphite Composites of Polytetrafluoroethylene (PTFE) Irradiated by the Electron Beam

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1676
Author(s):  
Adrian Barylski ◽  
Andrzej S. Swinarew ◽  
Krzysztof Aniołek ◽  
Sławomir Kaptacz ◽  
Jadwiga Gabor ◽  
...  
Keyword(s):  
Electron Beam ◽  
Young’S Modulus ◽  
Compression Strength ◽  
Electron Beam Irradiation ◽  
Young's Modulus ◽  
Degree Of Crystallinity ◽  
Beam Irradiation ◽  
Wear Properties ◽  
Graphite Content ◽  
Operational Life

This research investigated the effect of irradiation with an electron beam energy of 10 MeV in doses of 26–156 kGy on polytetrafluoroethylene (PTFE) with a 15% and 20% graphite additive. The research has shown that mechanical (compression strength, hardness, and Young’s modulus) and sclerometric (coefficient of wear micromechanism and coefficient of resistance to wear) properties improve and tribological wear decreases as graphite content increases. Electron beam irradiation increases the degree of crystallinity of both materials to a similar extent. However significant differences in the improvement of all examined properties have been demonstrated for PTFE with higher (20%) graphite content subjected to the electron beam irradiation. This polymer is characterized by higher hardness and Young’s modulus, reduced susceptibility to permanent deformation, higher elasticity, compression strength, and above all, a nearly 30% reduction in tribological wear compared to PTFE with a 15% graphite additive. The most advantageous properties can be obtained for both of the examined composites after absorbing a dose of 104 kGy. The obtained results hold promise for the improvement of the operational life of friction couples which do not require lubrication, used for example in air compressors and engines, and for the possibility of application of these modified polymers. In particular PTFE with 20% graphite content, in the nuclear and space industry.

scholarly journals Superior Interaction of Electron Beam Irradiation with Carbon Nanotubes Added Polyvinyl Alcohol Composite System

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4334
Author(s):  
Soo-Tueen Bee ◽  
Nicole Ooi Ker Qi ◽  
Lee Tin Sin ◽  
Hon-Meng Ng ◽  
Jun-Ven Lim ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Electron Beam ◽  
Polyvinyl Alcohol ◽  
Young’S Modulus ◽  
Electron Beam Irradiation ◽  
Composite System ◽  
Young's Modulus ◽  
Beam Irradiation ◽  
Crosslinked Networks ◽  
Adhesion Effect

This work was conducted to investigate the effect of carbon nanotube (CNT) on the mechanical-physico properties of the electron beam irradiated polyvinyl alcohol (PVOH) blends. The increasing of CNT amount up to 1.5 part per hundred resin (phr) has gradually improved tensile strength and Young’s modulus of PVOH/CNT nanocomposites due to effective interlocking effect of CNT particles in PVOH matrix, as evident in SEM observation. However, further increments of CNT, amounting up to 2 phr, has significantly decreased the tensile strength and Young’s modulus of PVOH/CNT nanocomposits due to the CNT agglomeration at higher loading level. Irradiation was found to effectively improve the tensile strength of PVOH/CNT nanocomposites by inducing the interfacial adhesion effect between CNT particles and PVOH matrix. This was further verified by the decrement values of d-spacing of the deflection peak. The increasing of CNT amounts from 0.5 phr to 1 phr has marginally induced the wavenumber of O–H stretching, which indicates the weakening of hydrogen bonding in PVOH matrix. However, further increase in CNT amounts up to 2 phr was observed to reduce the wavenumber of O–H stretching due to poor interaction effect between CNT and PVOH matrix. Electron beam irradiation was found to induce the melting temperature of all PVOH/CNT nanocomposite by inducing the crosslinked networks.

scholarly journals Novel Organic Material Induced by Electron Beam Irradiation for Medical Application

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 306 ◽  
Author(s):  
Adrian Barylski ◽  
Krzysztof Aniołek ◽  
Andrzej S. Swinarew ◽  
Sławomir Kaptacz ◽  
Jadwiga Gabor ◽  
...  
Keyword(s):  
Electron Beam ◽  
Electron Beam Irradiation ◽  
Absorbed Dose ◽  
Medical Application ◽  
High Energy ◽  
Polymer Chains ◽  
Degree Of Crystallinity ◽  
Beam Irradiation ◽  
The Impact ◽  
The Degree Of Crystallinity

This study analyzed the effects of irradiation of polytetrafluoroethylene (PTFE) containing 40% of bronze using an electron beam with energy of 10 MeV. Dosages from 26 to156 kGy (2.6–15.6 Mrad) were used. The impact of a high-energy electron beam on the thermal, spectrophotometric, mechanical, and tribological properties was determined, and the results were compared with those obtained for pure PTFE. Thermal properties studies showed that such irradiation caused changes in melting temperature Tm and crystallization temperature Tc, an increase in crystallization heat ∆Hc, and a large increase in crystallinity χc proportional to the absorbed dose for both polymers. The addition of bronze decreased the degree of crystallinity of PTFE by twofold. Infrared spectroscopy (FTIR) studies confirmed that the main phenomenon associated with electron beam irradiation was the photodegradation of the polymer chains for both PTFE containing bronze and pure PTFE. This had a direct effect on the increase in the degree of crystallinity observed in DSC studies. The use of a bronze additive could lead to energy dissipation over the additive particles. An increase in hardness H and Young’s modulus E was also observed. The addition of bronze and the irradiation with an electron beam improved of the operational properties of PTFE.

Methods to Monitor and Improve the Performance of Specimen Holders for Transmission Electron Cryomicroscopy

1996 ◽  
Vol 54 ◽  
pp. 454-455
Author(s):  
B. L. Armbruster ◽  
B. Kraus ◽  
M. Pan
Keyword(s):  
Electron Microscopy ◽  
Electron Beam ◽  
Electron Beam Irradiation ◽  
Beam Irradiation ◽  
Quality Of Data ◽  
Electron Cryomicroscopy ◽  
Thermal Equilibration ◽  
Transmission Electron ◽  
Electron Microscopes

One goal in electron microscopy of biological specimens is to improve the quality of data to equal the resolution capabilities of modem transmission electron microscopes. Radiation damage and beam- induced movement caused by charging of the sample, low image contrast at high resolution, and sensitivity to external vibration and drift in side entry specimen holders limit the effective resolution one can achieve. Several methods have been developed to address these limitations: cryomethods are widely employed to preserve and stabilize specimens against some of the adverse effects of the vacuum and electron beam irradiation, spot-scan imaging reduces charging and associated beam-induced movement, and energy-filtered imaging removes the “fog” caused by inelastic scattering of electrons which is particularly pronounced in thick specimens.Although most cryoholders can easily achieve a 3.4Å resolution specification, information perpendicular to the goniometer axis may be degraded due to vibration. Absolute drift after mechanical and thermal equilibration as well as drift after movement of a holder may cause loss of resolution in any direction.

A Study of Electron Beam Irradiation Influence on Device Contact Junction Characteristics of Advanced DRAM Using Atomic Force Probing

2013 ◽  
Author(s):  
Wei-Chih Wang ◽  
Jian-Shing Luo
Keyword(s):  
Electron Beam ◽  
Electron Beam Irradiation ◽  
Forward Bias ◽  
Irradiation Damage ◽  
Beam Irradiation ◽  
Excess Current ◽  
Atomic Force ◽  
Order Of Magnitude ◽  
Voltage Contrast ◽  
Acceleration Voltage

Abstract In this paper, we revealed p+/n-well and n+/p-well junction characteristic changes caused by electron beam (EB) irradiation. Most importantly, we found a device contact side junction characteristic is relatively sensitive to EB irradiation than its whole device characteristic; an order of magnitude excess current appears at low forward bias region after 1kV EB acceleration voltage irradiation (Vacc). Furthermore, these changes were well interpreted by our Monte Carlo simulation results, the Shockley-Read Hall (SRH) model and the Generation-Recombination (G-R) center trap theory. In addition, four essential examining items were suggested and proposed for EB irradiation damage origins investigation and evaluation. Finally, by taking advantage of the excess current phenomenon, a scanning electron microscope (SEM) passive voltage contrast (PVC) fault localization application at n-FET region was also demonstrated.

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