Microstructures and Properties of Ceramic Fibers of h-BN Containing Amorphous Si3N4

Composite ceramic fibers comprising about 80 wt% boron nitride (h-BN) and 20 wt% Si3N4 were fabricated through melt-spinning, electron-beam curing, and pyrolysis up to 1600 °C in atmospheres of NH3 and N2, using a mixture of poly[tri(methylamino)borazine] (PBN) and polysilazane (PSZ). By analyzing the microstructure and composition of the pyrolyzed ceramic fibers, we found the formation of binary phases including crystalline h-BN and amorphous Si3N4. Further investigations confirmed that this heterogeneous microstructure can only be formed when the introduced ratio of Si3N4 is below 30% in mass. The mean modulus and tensile strength of the fabricated composite fibers were about 90 GPa and 1040 MPa, twice the average of the pure h-BN fiber. The dielectric constant and dielectric loss tangent of the composite fibers is 3.06 and 2.94 × 10−3.

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Characterization and Microstructural Evolution of Continuous BN Ceramic Fibers Containing Amorphous Silicon Nitride

Materials ◽

10.3390/ma14206194 ◽

2021 ◽

Vol 14 (20) ◽

pp. 6194

Author(s):

Yang Li ◽

Min Ge ◽

Shouquan Yu ◽

Huifeng Zhang ◽

Chuanbing Huang ◽

...

Keyword(s):

Tensile Strength ◽

Silicon Nitride ◽

Melt Spinning ◽

Composite Ceramic ◽

Mass Content ◽

Composite Fibers ◽

Composite Ceramics ◽

Ceramic Fibers ◽

Amorphous Silicon Nitride ◽

The Mean

Boron nitride (BN) ceramic fibers containing amounts of silicon nitride (Si3N4) were prepared using hybrid precursors of poly(tri(methylamino)borazine) (PBN) and polycarbosilane (PCS) via melt-spinning, curing, decarburization under NH3 to 1000 °C and pyrolysis up to 1600 °C under N2. The effect of Si3N4 contents on the microstructure of the BN/Si3N4 composite ceramics was investigated. Series of the BN/Si3N4 composite fibers containing various amounts of Si3N4 from 5 wt% to 25 wt% were fabricated. It was found that the crystallization of Si3N4 could be totally restrained when its content was below 25 wt% in the BN/Si3N4 composite ceramics at 1600 °C, and the amorphous BN/Si3N4 composite ceramic could be obtained with a certain ratio. The mean tensile strength and Young’s modulus of the composite fibers correlated positively with the Si3N4 mass content, while an obvious BN (shell)/Si3N4 (core) was formed only when the Si3N4 content reached 25 wt%.

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Advances in SiC Fibers for High Temperature Applications

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.50.17 ◽

2006 ◽

Vol 50 ◽

pp. 17-23 ◽

Cited By ~ 5

Author(s):

Hiroshi Ichikawa

Keyword(s):

Thermal Stability ◽

Tensile Strength ◽

Elastic Modulus ◽

Creep Resistance ◽

Thermal Exposure ◽

High Tensile Strength ◽

Ceramic Fibers ◽

Sic Fiber ◽

Sic Composites ◽

Electron Beam Curing

The oxygen free SiC fiber (Hi-Nicalon) has been commercially produced by an electron beam curing process. And then the SiC fiber (Hi-Nicalon Type S) having stoichiometric SiC composition and high crystallinity has been developed. Hi-Nicalon fiber has higher elastic modulus and thermal stability than Nicalon fiber. The Type S fiber has the highest elastic modulus and thermal stability and excellent creep resistance in three types of Nicalon fibers. Recently，Type S fibers as industrial products have been developed and put on the market. The Type S fibers have a high tensile strength of 2.8 GPa, a high elastic modulus of 390 GPa. Against thermal exposure, Type S retains a tensile strength of 2.3 GPa and hardly changes its elastic modulus even at 1873K. Moreover, Type S has outstanding creep resistance. Type S shows higher stress relaxation ratio than many other ceramic fibers after thermal exposure over 1673K. Now, Hi-Nicalon Type S fiber/BN/SiC composites are being developed as the components of gas turbine for aerospace and land based power generation such as shrouds and combustors. Type Hi-Nicalon S can be supplied about 30 kg per a month at present.

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Properties of High-Performance Porous SiOC Low-kFilm Fabricated Using Electron-Beam Curing

Japanese Journal of Applied Physics ◽

10.1143/jjap.44.3872 ◽

2005 ◽

Vol 44 (6A) ◽

pp. 3872-3878 ◽

Cited By ~ 24

Author(s):

Takashi Yoda ◽

Keiji Fujita ◽

Hideshi Miyajima ◽

Rempei Nakata ◽

Naoto Miyashita ◽

...

Keyword(s):

Electron Beam ◽

High Performance ◽

Electron Beam Curing

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The Structure and Mechanical Properties of Hemp Fibers-Reinforced Poly(ε-Caprolactone) Composites Modified by Electron Beam Irradiation

Applied Sciences ◽

10.3390/app11125317 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5317

Author(s):

Rafał Malinowski ◽

Aneta Raszkowska-Kaczor ◽

Krzysztof Moraczewski ◽

Wojciech Głuszewski ◽

Volodymyr Krasinskyi ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Electron Beam ◽

Impact Strength ◽

Flexural Modulus ◽

Natural Fibers ◽

High Energy ◽

Electron Radiation ◽

Elongation At Break ◽

Hemp Fibers

The need for the development of new biodegradable materials and modification of the properties the current ones possess has essentially increased in recent years. The aim of this study was the comparison of changes occurring in poly(ε-caprolactone) (PCL) due to its modification by high-energy electron beam derived from a linear electron accelerator, as well as the addition of natural fibers in the form of cut hemp fibers. Changes to the fibers structure in the obtained composites and the geometrical surface structure of sample fractures with the use of scanning electron microscopy were investigated. Moreover, the mechanical properties were examined, including tensile strength, elongation at break, flexural modulus and impact strength of the modified PCL. It was found that PCL, modified with hemp fibers and/or electron radiation, exhibited enhanced flexural modulus but the elongation at break and impact strength decreased. Depending on the electron radiation dose and the hemp fibers content, tensile strength decreased or increased. It was also found that hemp fibers caused greater changes to the mechanical properties of PCL than electron radiation. The prepared composites exhibited uniform distribution of the dispersed phase in the polymer matrix and adequate adhesion at the interface between the two components.

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Dynamic Single-Fiber Pull-Out of Polypropylene Fibers Produced with Different Mechanical and Surface Properties for Concrete Reinforcement

Materials ◽

10.3390/ma14040722 ◽

2021 ◽

Vol 14 (4) ◽

pp. 722

Author(s):

Enrico Wölfel ◽

Harald Brünig ◽

Iurie Curosu ◽

Viktor Mechtcherine ◽

Christina Scheffler

Keyword(s):

Tensile Strength ◽

Dynamic Loading ◽

Melt Spinning ◽

Structural Changes ◽

High Surface ◽

Single Fiber ◽

Scanning Calorimetry ◽

Matrix Interaction ◽

Pull Out ◽

Fiber Matrix

In strain-hardening cement-based composites (SHCC), polypropylene (PP) fibers are often used to provide ductility through micro crack-bridging, in particular when subjected to high loading rates. For the purposeful material design of SHCC, fundamental research is required to understand the failure mechanisms depending on the mechanical properties of the fibers and the fiber–matrix interaction. Hence, PP fibers with diameters between 10 and 30 µm, differing tensile strength levels and Young’s moduli, but also circular and trilobal cross-sections were produced using melt-spinning equipment. The structural changes induced by the drawing parameters during the spinning process and surface modification by sizing were assessed in single-fiber tensile experiments and differential scanning calorimetry (DSC) of the fiber material. Scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle measurements were applied to determine the topographical and wetting properties of the fiber surface. The fiber–matrix interaction under quasi-static and dynamic loading was studied in single-fiber pull-out experiments (SFPO). The main findings of microscale characterization showed that increased fiber tensile strength in combination with enhanced mechanical interlocking caused by high surface roughness led to improved energy absorption under dynamic loading. Further enhancement could be observed in the change from a circular to a trilobal fiber cross-section.

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Directionally-Dependent Mechanical Properties of Ti6Al4V Manufactured by Electron Beam Melting (EBM) and Selective Laser Melting (SLM)

Materials ◽

10.3390/ma14133603 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3603

Author(s):

Tim Pasang ◽

Benny Tavlovich ◽

Omry Yannay ◽

Ben Jakson ◽

Mike Fry ◽

...

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Tensile Strength ◽

Electron Beam ◽

Additive Manufacturing ◽

Selective Laser Melting ◽

Electron Beam Melting ◽

Rolling Direction ◽

Laser Melting ◽

Plate Rolling

An investigation of mechanical properties of Ti6Al4V produced by additive manufacturing (AM) in the as-printed condition have been conducted and compared with wrought alloys. The AM samples were built by Selective Laser Melting (SLM) and Electron Beam Melting (EBM) in 0°, 45° and 90°—relative to horizontal direction. Similarly, the wrought samples were also cut and tested in the same directions relative to the plate rolling direction. The microstructures of the samples were significantly different on all samples. α′ martensite was observed on the SLM, acicular α on EBM and combination of both on the wrought alloy. EBM samples had higher surface roughness (Ra) compared with both SLM and wrought alloy. SLM samples were comparatively harder than wrought alloy and EBM. Tensile strength of the wrought alloy was higher in all directions except for 45°, where SLM samples showed higher strength than both EBM and wrought alloy on that direction. The ductility of the wrought alloy was consistently higher than both SLM and EBM indicated by clear necking feature on the wrought alloy samples. Dimples were observed on all fracture surfaces.

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Organic/inorganic nanocomposite coating of bisphenol A diglycidyl ether diacrylate containing silica nanoparticles via electron beam curing process

Progress in Organic Coatings ◽

10.1016/j.porgcoat.2013.03.010 ◽

2013 ◽

Vol 76 (7-8) ◽

pp. 1119-1126 ◽

Cited By ~ 17

Author(s):

Virendra Kumar ◽

N. Misra ◽

Jhimli Paul ◽

Y.K. Bhardwaj ◽

N.K. Goel ◽

...

Keyword(s):

Electron Beam ◽

Bisphenol A ◽

Silica Nanoparticles ◽

Nanocomposite Coating ◽

Diglycidyl Ether ◽

Curing Process ◽

Bisphenol A Diglycidyl Ether ◽

Electron Beam Curing

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Starch-Based Fishing Composite Fiber and Its Degradation Behavior

International Journal of Polymer Science ◽

10.1155/2020/9209108 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Wenwen Yu ◽

Fei Yang ◽

Lei Wang ◽

Yongli Liu ◽

Jiangao Shi

Keyword(s):

Melt Spinning ◽

Starch Content ◽

Reactive Extrusion ◽

Composite Fiber ◽

Mechanical Analysis ◽

Composite Fibers ◽

Reactive Blending ◽

Dynamic Mechanical ◽

One Step ◽

Β Relaxation

The starch-based fishing composite fibers were prepared by one-step reactive extrusion and melt spinning. The effects of starch contents on the microstructural, thermal, dynamic mechanical, and mechanical properties of starch-based composite fibers were studied. And the degradation behaviors in soil of the fibers were also investigated. The compatibility between starch and HDPE is improved significantly by grafting maleic anhydride (MA) using one-step reactive blending extrusion. As the starch content increased, the melting temperature and the crystallinity of the fibers gradually decreased due to fluffy internal structures. Dynamic mechanical analysis showed that the transition peak α in the high-temperature region was gradually weakened and narrowed with increasing starch content; moreover, a shoulder appeared on the low-temperature side of the α peak was assigned to the β-relaxation related to starch phase. In addition, the mechanical results showed the significant decrease in the breaking strength and increase in the elongation at break of the starch-based composite fibers as the starch content increased. After degradation in soil for 5 months, the surface of the composite fibers had been deteriorated, while flocculent layers were observed and a large number of microfibers appeared. And the weight loss rate of the starch-based composite fibers (5.2~34.8%) significantly increased with increasing starch content (50~90 wt%).

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Silicon Carbide Base Ceramic Fiber Synthesis from Polycarbosilane-Modified Polymethylsilane Blend Polymers by Melt Spinning

Materials Science Forum ◽

10.4028/www.scientific.net/msf.675-677.139 ◽

2011 ◽

Vol 675-677 ◽

pp. 139-142

Author(s):

Xin Xing ◽

Lin Liu ◽

Feng Cao ◽

Xiao Dong Li ◽

Zeng Yong Chu ◽

...

Keyword(s):

Silicon Carbide ◽

Tensile Strength ◽

Thermal Oxidation ◽

Melt Spinning ◽

Ceramic Fiber ◽

Ceramic Yield ◽

Base Ceramic

A melt-spinnable precursor for SiC based fibers was prepared from blend polymers of polycarbosilane (PCS) and modified polymethylsilane (M-PMS). The blend polymers cured at 320°C are different from M-PMS and PCS. The ceramic yield of these blend polymers is about 83%. The C/Si ratio of M-PMS/PCS derived ceramics (pyrolyzed at 1250°C) is linear to the content of MPMS in M-PMS/PCS. After melt spinning, thermal oxidation curing, and pyrolysis, Si-C-O fibers were obtained. The diameter and the tensile strength of the resulted fibers are 16.5μm and 1.62GPa, respectively.

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