Comparison of DC and AC Surface Breakdown Characteristics of GFRP and Epoxy Nanocomposites in Liquid Nitrogen

Koo, Ja-Yoon; Hwang, Jae Sang; Shin, Woo Ju; Sakamoto, Kuniaki; Oh, Dong-Hun; Lee, Bang-Wook

doi:10.1109/tasc.2016.2544104

Cited by 10 publications

(7 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although the epoxy nanocomposites are more frequently employed because of their good electrical properties, they are also suggested as insulating materials [ 52 , 149 ]. Some nanofillers found an application for electrostatic discharge purposes (e.g., in aircraft applications).…”

Section: Applications Of Nanofilled/nanostructured Epoxy Resinsmentioning

confidence: 99%

“…Due to their outstanding mechanical, thermal, and electrical properties, these multilayered compounds have been employed to realize multifunctional epoxy-based nanocomposites characterized by enhanced electrical and thermal conductivity, self-healing characteristics, excellent toughness, and mechanical properties, even at low filler percentages (1 wt.%) [46][47][48][49][50]. The positive effects of the nano-Al2O3, especially on mechanical properties (the nanoparticles are able to significantly increase the strength at the fiber/matrix interface [52]), can be found also when these particles are added in fiber reinforced composites based on an epoxy matrix, even at very low contents (i.e., 1-0.5 wt.%) [53][54][55]. The beneficial effects of nanoalumina are also reported in the field of epoxy adhesives [51,56,57].…”

Section: Carbon-based Nanofillersmentioning

confidence: 99%

“…Furthermore, the addition of even low loads (1-2.5 wt.%) of epoxy-grafted nanosilica brings about enhancements in mechanical and dielectric strength, as well as reductions in the water uptake [66]. The positive effects of the nano-Al 2 O 3 , especially on mechanical properties (the nanoparticles are able to significantly increase the strength at the fiber/matrix interface [52]), can be found also when these particles are added in fiber reinforced composites based on an epoxy matrix, even at very low contents (i.e., 1-0.5 wt.%) [53][54][55]. The beneficial effects of nanoalumina are also reported in the field of epoxy adhesives [51,56,57].…”

Section: Metal Oxides and Othermentioning

confidence: 99%

See 2 more Smart Citations

Recent Advances and Trends of Nanofilled/Nanostructured Epoxies

Frigione

Lettieri

2020

Materials

View full text Add to dashboard Cite

This paper aims at reviewing the works published in the last five years (2016–2020) on polymer nanocomposites based on epoxy resins. The different nanofillers successfully added to epoxies to enhance some of their characteristics, in relation to the nature and the feature of each nanofiller, are illustrated. The organic–inorganic hybrid nanostructured epoxies are also introduced and their strong potential in many applications has been highlighted. The different methods and routes employed for the production of nanofilled/nanostructured epoxies are described. A discussion of the main properties and final performance, which comprise durability, of epoxy nanocomposites, depending on chemical nature, shape, and size of nanoparticles and on their distribution, is presented. It is also shown why an efficient uniform dispersion of the nanofillers in the epoxy matrix, along with strong interfacial interactions with the polymeric network, will guarantee the success of the application for which the nanocomposite is proposed. The mechanisms yielding to the improved properties in comparison to the neat polymer are illustrated. The most important applications in which these new materials can better exploit their uniqueness are finally presented, also evidencing the aspects that limit a wider diffusion.

show abstract

Section: Applications Of Nanofilled/nanostructured Epoxy Resinsmentioning

confidence: 99%

Section: Carbon-based Nanofillersmentioning

confidence: 99%

Section: Metal Oxides and Othermentioning

confidence: 99%

See 1 more Smart Citation

Recent Advances and Trends of Nanofilled/Nanostructured Epoxies

Frigione

Lettieri

2020

Materials

View full text Add to dashboard Cite

show abstract

“…Since the application of alternating current (ac) in power transmission began in the late 19 th century, it has been realized that the dc breakdown strength is about twice or higher than the ac breakdown strength in insulating materials 1 . Throughout the 20 th century, many investigations on this phenomenon were conducted 1 2 3 4 5 6 7 8 9 10 and it was discovered that this phenomenon commonly exists in many insulating materials, from thin films to thick boards 3 . From the early 20 th century on, now-classical theories such as electrical breakdown (introduced by Hipple in 1937 11 and Fröhlich in 1939 12 ) and thermal breakdown 13 (introduced by Wagner in 1922) have been proposed.…”

mentioning

confidence: 99%

Space Charge Modulated Electrical Breakdown

Zhu

Min

2016

Sci Rep

View full text Add to dashboard Cite

Electrical breakdown is one of the most important physical phenomena in electrical and electronic engineering. Since the early 20th century, many theories and models of electrical breakdown have been proposed, but the origin of one key issue, that the explanation for dc breakdown strength being twice or higher than ac breakdown strength in insulating materials, remains unclear. Here, by employing a bipolar charge transport model, we investigate the space charge dynamics in both dc and ac breakdown processes. We demonstrate the differences in charge accumulations under both dc and ac stresses and estimate the breakdown strength, which is modulated by the electric field distortion induced by space charge. It is concluded that dc breakdown initializes in the bulk whereas ac breakdown initializes in the vicinity of the sample-electrode interface. Compared with dc breakdown, the lower breakdown strength under ac stress and the decreasing breakdown strength with an increase in applied frequency, are both attributed to the electric field distortion induced by space charges located in the vicinity of the electrodes.

show abstract

“…However, because the surface of nano-particle filler is quite different from that of epoxy resin matrix, agglomeration is easy to occur during the preparation process, which will result in a decrease in the breakdown resistance of composites. J. H. Koo et al found that modification of nano-filler under LN 2 did not significantly increase the AC/DC interfacial breakdown voltage of epoxy nanocomposites [ 20 ].…”

Section: Introductionmentioning

confidence: 99%

Study on Surface Discharge Characteristics of GO-Doped Epoxy Resin–LN2 Composite Insulation

et al. 2022

View full text Add to dashboard Cite

Superconducting power lead equipment for epoxy insulation, such as high-temperature superconducting DC power or liquefied natural gas energy pipelines, as well as high-temperature superconducting cables, has long been used in extreme environments, from liquid nitrogen temperatures to normal temperatures. It is easy to induce surface discharge and flashover under the action of strong electric field, which accelerates the insulation failure of current leads. In this paper, two-dimensional nano-material GO was used to control the electrical properties of epoxy resins. The DC surface discharge and flashover characteristics of the prepared epoxy resin–GO composite insulation materials were tested at room temperature with liquid nitrogen. The surface discharge mechanism of the epoxy resin–GO composite insulation materials was analyzed. The experimental results show that the insulation properties of epoxy composites doped with GO changed. Among them, the surface flashover voltage of 0.05 wt% material is the best, which can inhibit the discharge phenomenon and improve its insulation properties in extreme environments, from room temperature to liquid nitrogen temperature. It is found that the development process of surface discharge of composite insulating materials under liquid nitrogen is quite different from that under room temperature. Before critical flashover, the repetition rate and amplitude of surface discharge remain at a low level until critical flashover. Furthermore, the voltage of the first flashover is significantly higher than that of the subsequent flashover under the action of the desorption gas on the surface of the composite insulating material and the gasification layer produced by the discharge. Given that the surface flashover voltage of 0.05 wt% epoxy composite is the best, the research and analysis of 0.05 wt% composite is emphasized. In the future design of superconducting power lead insulation, the modification method of adding GO to epoxy resin can be considered in order to improve its insulation performance.

show abstract

Comparison of DC and AC Surface Breakdown Characteristics of GFRP and Epoxy Nanocomposites in Liquid Nitrogen

Cited by 10 publications

References 9 publications

Recent Advances and Trends of Nanofilled/Nanostructured Epoxies

Recent Advances and Trends of Nanofilled/Nanostructured Epoxies

Space Charge Modulated Electrical Breakdown

Study on Surface Discharge Characteristics of GO-Doped Epoxy Resin–LN2 Composite Insulation

Contact Info

Product

Resources

About