Electrical treeing studies on the Araldite LY/HY 5052 epoxy resin over a wide range of stressing voltage

Epoxy resin-based composite panels used for armors may be subjected to a wide range of operating temperatures (-55°C to 76°C) and high strain rates on the order of 103-104 s-1. Over the life cycle, various environmental factors also affect the resin properties and hence influence the performance of the composites. Therefore, it is critical to determine the stress-strain behavior of the epoxy resin over a wide range of strain rates and temperatures for accurate multi-scale modeling of composites and to investigate the influence of environmental aging on the resin properties. Additionally, the characterization of key mechanical properties such as yield stress, modulus, and energy absorption (i.e. area under the stress-strain curve) at varying temperatures and moisture can provide critical data to calculate the material operating limits. In this study, we characterize mechanical properties of neat epoxy resin, SC-15 (currently used in structural armor) and RDL-RDC using uniaxial compression testing. RDL-RDC, developed by Huntsman Corporation, has a glass transition temperature of ~ 120°C, compared to ~ 85°C of SC-15. A split Hopkinson pressure bar is used for high strain rate testing. Quasistatic testing is conducted using a screw-driven testing machine (Instron 4484) at 10-3 s-1 and 10-1 s-1 strain rates and varying temperatures. The yield stress is fit to a modified Eyring model over the varying strain rates at room temperature. For rapid investigation of resistance to environmental aging, accelerated aging tests are conducted by immersing the specimens in 100°C water for 48 hours. Specimens are conditioned in an environmental chamber at 76 °C and 88% RH until they reach equilibrium. Tests are then conducted at five different temperatures from 0°C to 95°C, and key mechanical properties are then plotted vs. temperature. The results presented are an important step towards developing a methodology to identify environmental operating conditions for composite ground vehicle applications.

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The role of power quality in electrical treeing of epoxy resin

2007 Annual Report - Conference on Electrical Insulation and Dielectric Phenomena ◽

10.1109/ceidp.2007.4451500 ◽

2007 ◽

Cited By ~ 2

Author(s):

S. Bahadoorsingh ◽

S. M. Rowland

Keyword(s):

Epoxy Resin ◽

Power Quality ◽

Electrical Treeing

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Electrical treeing in a glassy epoxy resin — The filamentary tree and the PD tree

2017 IEEE Conference on Electrical Insulation and Dielectric Phenomenon (CEIDP) ◽

10.1109/ceidp.2017.8257517 ◽

2017 ◽

Cited By ~ 3

Author(s):

Hualong Zheng ◽

Simon M. Rowland

Keyword(s):

Epoxy Resin ◽

Electrical Treeing

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A Low-Cost Current Sensor Based on Semi-Cylindrical Magnetostrictive Composite

Electronics ◽

10.3390/electronics9111833 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1833

Author(s):

Shaoyi Xu ◽

Qiang Peng ◽

Fangfang Xing ◽

Hongyu Xue ◽

Junwen Sun ◽

...

Keyword(s):

Particle Size ◽

Epoxy Resin ◽

Low Cost ◽

High Sensitivity ◽

Current Sensor ◽

Mass Ratio ◽

Particle Size Range ◽

Giant Magnetostrictive Material ◽

Wide Range ◽

Magnetostrictive Composites

This paper presents the design, fabrication, and characterization of a compact current sensor based on magnetostrictive composites and resistance strain gauges. Firstly, we designed three kinds of current sensors with different structures, in which the shape of the giant magnetostrictive material (GMM) was cuboid, cylindrical, and semi-cylindrical. A set of finite element method (FEM) simulations were performed to qualitatively guide the design of three prototypes of the current sensor. It was determined that the most ideal shape of the GMM was semi-cylindrical. Secondly, Terfenol-D (TD) powder and epoxy resin were mixed to prepare magnetostrictive composites. In this paper, magnetostrictive composites with different particle size ranges and mass ratio were prepared and tested. The results show that the magnetostrictive composites had the best performance when the particle size range was 149–500 μm and the mass ratio of epoxy resin to TD powder was 1:5. Finally, this paper tested the performance of the sensor. The sensitivity, repeatability, and linear working range of the sensor reached 0.104 με/A, 2.51%, and 100–900 A respectively, when only 0.31 g of TD powder was employed. This means that current measurement with low cost, high sensitivity, and wide range was realized.

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Permittivity and Loss of Composites of Epoxy Resin and Kevlar Fibres

Advanced Composites Letters ◽

10.1177/096369359500400405 ◽

1995 ◽

Vol 4 (4) ◽

pp. 096369359500400 ◽

Cited By ~ 1

Author(s):

G.M. Tsangaris ◽

G.C. Psarras

Keyword(s):

Dielectric Permittivity ◽

Epoxy Resin ◽

Filler Content ◽

Low Frequency ◽

Interfacial Polarization ◽

Dielectric Behaviour ◽

Frequency Range ◽

Wide Range ◽

Dielectric Permittivity And Loss

The dielectric behaviour of composites with epoxy resin and kevlar fibres is investigated in a wide range of frequency and temperature. Dielectric permittivity is increasing with filler content and temperature, being always higher in the low frequency range. Dielectric permittivity and loss of the composites is mostly affected by interfacial polarization arising from inhomogeneities at interfaces introduced by the filler.

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Electrical Treeing Growth and Partial Discharge Characteristics in Epoxy Resin Filled with Micro Particles

IEEJ Transactions on Fundamentals and Materials ◽

10.1541/ieejfms.139.337 ◽

2019 ◽

Vol 139 (7) ◽

pp. 337-338

Author(s):

Takaki Yokoi ◽

Akiko Kumada ◽

Kunihiko Hidaka ◽

Tatsuro Kato ◽

Tokio Yamagiwa

Keyword(s):

Epoxy Resin ◽

Partial Discharge ◽

Discharge Characteristics ◽

Micro Particles ◽

Electrical Treeing

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Investigation on Mechanical, Thermal and Bonding Properties of MWCNTs Reinforced Aramid/Epoxy Composite

Nano Hybrids and Composites ◽

10.4028/www.scientific.net/nhc.30.27 ◽

2020 ◽

Vol 30 ◽

pp. 27-40

Author(s):

Naresh Kumar Konada ◽

K.N.S. Suman ◽

Roop Sandeep Bammidi ◽

B.B.Ashok Kumar

Keyword(s):

Epoxy Resin ◽

Polymer Matrix ◽

Research Work ◽

Graphite Powder ◽

Friction Material ◽

Aramid Fiber ◽

Bonding Performance ◽

Wide Range ◽

Bonding Properties ◽

Grain Distribution

The poor ability of bonding performance of aramid fiber with epoxy resin limits its usage for wide range of applications. In this research work, an attempt was made to improve the bonding performance of aramid fiber with polymer matrix by performing nitric acid treatment on fiber. The role of functionalized multi walled carbon nano tubes (F-MWCNTs) reinforced in the base polymer matrix is also studied. Six composite sheets (AF0, AF1, AF2, AF3, AF4, and AF5) with varying content of F-MWCNTs from (0.1wt% to 0.5wt %) are fabricated using hand layup method having dimensions of 25cm x 25 cm x 0.8 cm . AF0 composite sheet is free from presence of F-MWCNTs. The remaining ingredients [80% epoxy resin, 0.2 % rubber powder, 0.2% graphite powder, and 0.2% BaSO4, 0.2% Zirconium Silicate powder and 1.5 % fiber] are kept constant for achieving desirable properties of friction materials. After undergoing, curing process in atmosphere for 72 hrs, the specimens are cut according to ASTM standards to evaluate mechanical, thermal and bonding properties of the composites. Scanning electron microscope images (SEM) are observed for the samples to observe the grain distribution present in the composite. It was observed from results that, AF4 (aramid fiber reinforced composite friction material with 0.4% F-MWCNTs inclusions ) along with remaining ingredients exhibited better mechanical ,thermal and bonding properties compared to remaining formulations of materials.

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