Hygrothermal aging effect on the properties of PMMA nanocomposites reinforced by ceramic nanoparticles

This paper aimed to evaluate hygrothermal aging effects on polymethyl methacrylate modified with TiO2, SiO2, and Al2O3 nanoparticles in 0.5, 1, and 2% weight fractions. The distribution of nanoparticles was characterized by the scanning electron microscopy (SEM) method. Moisture absorption behavior and mechanical properties of samples in terms of elastic modulus, tensile strength, impact strength, and hardness were investigated. Furthermore, the coefficient of hygrothermal expansion (CHE) for each sample was calculated thanks to experimental data. Finally, by applying the multi-criteria decision making (MCDM) technique, the optimum composition for superior performance was obtained in 0.5 wt% of nanoparticles, more specifically for SiO2.

Comparison of Particle Size Analyses from FEG-SEM and TEM Images

Microscopy and Microanalysis ◽

10.1017/s1431927600034395 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 380-381

Author(s):

S. Lanteri ◽

D. Gendt ◽

P. Barges ◽

G. Petitgand

Keyword(s):

Electron Microscopy ◽

Experimental Data ◽

Mechanical Properties ◽

Size Range ◽

Experimental Measurements ◽

Mechanical Processing ◽

Size Distributions ◽

Heat Treated ◽

Steel Properties ◽

Much effort has recently been employed in modeling steel behavior as a function of chemical composition and thermo-mechanical processing. In order for the models to be predictive, experimental data are needed to first calibrate and then validate the calculated results. Since many steel properties are conditioned in part by the state of precipitation, this study was undertaken to provide experimental measurements of precipitates in terms of their size distributions. Due to the size range (2-100 nm) of particles which exert the greatest influence on the mechanical properties, electron microscopy is practically the only technique available for obtaining images of the precipitates.Two types of micrographs were used for image analysis in order to determine the size distribution of NbC particles present in a ternary alloy (Fe-Nb-C) heat treated at 800°C for 1000 mn. Polished surfaces lightly etched with a solution of 2% HNO3 and 98% ethanol were prepared for observations in a LEO 1550 scanning electron microscope equipped with a field emission gun.

Electron Microscopic Observation of the Longitudinal Organization of Poly (p-Phenylene Terephthalamide) Fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055734 ◽

1982 ◽

Vol 40 ◽

pp. 680-681

Author(s):

Li Li-Sheng ◽

L.F. Allard ◽

W.C. Bigelow

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Microscopic Observation ◽

Electron Microscopic Observation ◽

Electron Microscopic ◽

Aromatic Polyamides ◽

Radial Arrangement ◽

Scanning Electron ◽

Better Than

The aromatic polyamides form a class of fibers having mechanical properties which are much better than those of aliphatic polyamides. Currently, the accepted morphology of these fibers as proposed by M.G. Dobb, et al. is a radial arrangement of pleated sheets, with the plane of the pleats parallel to the axis of the fiber. We have recently obtained evidence which supports a different morphology of this type of fiber, using ultramicrotomy and ion-thinning techniques to prepare specimens for transmission and scanning electron microscopy.

Analysis of PLA Composite Filaments Reinforced with Lignin and Polymerised-Lignin-Treated NFC

Polymers ◽

10.3390/polym13132174 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2174

Author(s):

Diana Gregor-Svetec ◽

Mirjam Leskovšek ◽

Blaž Leskovar ◽

Urška Stanković Elesini ◽

Urška Vrabič-Brodnjak

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Tensile Strength ◽

Glassy State ◽

Nanofibrillated Cellulose ◽

Dynamic Mechanical Properties ◽

Initial Modulus ◽

Surface Modified ◽

Polylactic acid (PLA) is one of the most suitable materials for 3D printing. Blending with nanoparticles improves some of its properties, broadening its application possibilities. The article presents a study of composite PLA matrix filaments with added unmodified and lignin/polymerised lignin surface-modified nanofibrillated cellulose (NFC). The influence of untreated and surface-modified NFC on morphological, mechanical, technological, infrared spectroscopic, and dynamic mechanical properties was evaluated for different groups of samples. As determined by the stereo and scanning electron microscopy, the unmodified and surface-modified NFCs with lignin and polymerised lignin were present in the form of plate-shaped agglomerates. The addition of NFC slightly reduced the filaments’ tensile strength, stretchability, and ability to absorb energy, while in contrast, the initial modulus slightly improved. By adding NFC to the PLA matrix, the bending storage modulus (E’) decreased slightly at lower temperatures, especially in the PLA samples with 3 wt% and 5 wt% NFC. When NFC was modified with lignin and polymerised lignin, an increase in E’ was noticed, especially in the glassy state.

Phase Relations in the ZrO2-MgO-FeOx System: Experimental Data and Assessment of Thermodynamic Parameters

Journal of Phase Equilibria and Diffusion ◽

10.1007/s11669-021-00876-y ◽

2021 ◽

Author(s):

Ivan Saenko ◽

O. Fabrichnaya

Keyword(s):

Electron Microscopy ◽

Experimental Data ◽

Solid Solution ◽

Thermodynamic Parameters ◽

Spinel Phase ◽

Experimental Investigations ◽

X Ray ◽

Heat Treated ◽

Preliminary Phase ◽

AbstractThermodynamic parameters were assessed for the MgO–FeOx system and combined with already available descriptions of ZrO2-FeOx and ZrO2-MgO systems to calculate preliminary phase diagrams for planning experimental investigations. Samples of selected compositions were heat treated at 1523, 1673 and 1873 K and characterized using x-ray and scanning electron microscopy combined with energy dispersive x-ray spectroscopy (SEM/EDX). Experiments indicated extension of cubic ZrO2 solid solution into the ternary system at 1873 K (75 mol.% ZrO2, 10 mol.% FeOx and 15 mol.% MgO) and limited solubility of 4 mol.% ZrO2 in spinel phase. Based on the obtained results thermodynamic parameters of C-ZrO2 and spinel phase were optimized.

Corrosion Behavior and Mechanical Properties of a Nanocomposite Superhydrophobic Coating

Coatings ◽

10.3390/coatings11060652 ◽

2021 ◽

Vol 11 (6) ◽

pp. 652

Author(s):

Divine Sebastian ◽

Chun-Wei Yao ◽

Lutfun Nipa ◽

Ian Lian ◽

Gary Twu

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Atomic Force Microscopy ◽

Nanocomposite Coating ◽

Superhydrophobic Coating ◽

Force Microscopy ◽

Atomic Force ◽

Microscopy Images ◽

In this work, a mechanically durable anticorrosion superhydrophobic coating is developed using a nanocomposite coating solution composed of silica nanoparticles and epoxy resin. The nanocomposite coating developed was tested for its superhydrophobic behavior using goniometry; surface morphology using scanning electron microscopy and atomic force microscopy; elemental composition using energy dispersive X-ray spectroscopy; corrosion resistance using atomic force microscopy; and potentiodynamic polarization measurements. The nanocomposite coating possesses hierarchical micro/nanostructures, according to the scanning electron microscopy images, and the presence of such structures was further confirmed by the atomic force microscopy images. The developed nanocomposite coating was found to be highly superhydrophobic as well as corrosion resistant, according to the results from static contact angle measurement and potentiodynamic polarization measurement, respectively. The abrasion resistance and mechanical durability of the nanocomposite coating were studied by abrasion tests, and the mechanical properties such as reduced modulus and Berkovich hardness were evaluated with the aid of nanoindentation tests.

Effect of Sintering Temperature on Microstructure and Mechanical Properties of Al2O3-TiC-ZrO2 Ceramic Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.1031 ◽

2012 ◽

Vol 476-478 ◽

pp. 1031-1035

Author(s):

Wei Min Liu ◽

Xing Ai ◽

Jun Zhao ◽

Yong Hui Zhou

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Fracture Toughness ◽

Flexural Strength ◽

Relative Density ◽

Sintering Temperature ◽

Ceramic Composites ◽

X Ray Diffraction ◽

X Ray ◽

Al2O3-TiC-ZrO2ceramic composites (ATZ) were fabricated by hot-pressed sintering. The phases and microstructure of the composites were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The relative density and mechanical properties (flexural strength, fracture toughness and Vicker’s hardness) of the composites were tested. The results show that the microstructure of the composites was the gray core-white rim. With the increase of sintering temperature, the relative density and mechanical properties of the composites increased first and then decreased. The composite sintered at 1705°C has the highest synthetical properties, and its relative density, flexural strength, fracture toughness and Vickers hardness are 98.3%,970MPa,6.0 MPa•m1/2and 20.5GPa, respectively.

Research on compatibility and surface of high impact bio-based polyamide

High Performance Polymers ◽

10.1177/09540083211005511 ◽

2021 ◽

pp. 095400832110055

Author(s):

Yang Wang ◽

Yuhui Zhang ◽

Yuhan Xu ◽

Xiucai Liu ◽

Weihong Guo

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Differential Scanning Calorimetry ◽

Crystallization Behavior ◽

High Impact ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

The super-tough bio-based nylon was prepared by melt extrusion. In order to improve the compatibility between bio-based nylon and elastomer, the elastomer POE was grafted with maleic anhydride. Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA) were used to study the compatibility and micro-distribution between super-tough bio-based nylon and toughened elastomers. The results of mechanical strength experiments show that the 20% content of POE-g-MAH has the best toughening effect. After toughening, the toughness of the super-tough nylon was significantly improved. The notched impact strength was 88 kJ/m2 increasing by 1700%, which was in line with the industrial super-tough nylon. X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) were used to study the crystallization behavior of bio-based PA56, and the effect of bio-based PA56 with high crystallinity on mechanical properties was analyzed from the microstructure.

Microstructure Evolution and Mechanical Properties of an Al-Cu-Mg Alloy at Elevated Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1004-1005.148 ◽

2014 ◽

Vol 1004-1005 ◽

pp. 148-153

Author(s):

Min Hao ◽

Ji Gang Ru ◽

Ming Liu ◽

Kun Zhang ◽

Liang Wang ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Elevated Temperature ◽

Elevated Temperatures ◽

Shear Fracture ◽

S Phase ◽

Mg Alloy ◽

Transmission Electron ◽

Fracture Features ◽

Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to study the microstructure and mechanical behavior of an Al-Cu-Mg alloy after tensile test at 125°C, 150°C, 175°C and 200 °C, respectively. The yield strength and ultimate tensile strength decreased with the increase of temperature, while the elongation increased firstly and then decreased. The S and S′ precipitate after tension at elevated temperatures. When the temperature was higher than 175°C, the precipitate coarsens rapidly. The alloys displayed a shear fracture features at elevated temperature. The larger S′ and S phase coarsened and dropped which forming crack in the grain boundaries and precipitate interfaces, resulting in the decrease of the elongation of the alloy.

Effect of Annealing Process on the Mechanical Properties of X70 Pipeline Steel

MATEC Web of Conferences ◽

10.1051/matecconf/201818602001 ◽

2018 ◽

Vol 186 ◽

pp. 02001

Author(s):

Teng-wei Zhu ◽

Cheng-liang Miao ◽

Zheng Cheng ◽

Zhipeng Wang ◽

Yang Cui ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Tensile Strength ◽

Annealing Temperature ◽

Pipeline Steel ◽

Annealing Process ◽

X70 Pipeline Steel ◽

Grain Sizes ◽

The influence of the mechanical properties of X70 pipeline steel under different annealing temperature was studied. The corresponding microstructure was investigated by the Field Emission Scanning Electron Microscopy. The results showed that the yield strength and the tensile strength both experienced from rise to decline with the increase of annealing temperature. The grain sizes were coarse and a large amount of cementite precipitated due to preserving temperature above 550 °, which induced matrix fragmentation and deteriorate the -10 ° DWTT Toughness. There were little changes on the microstructure and mechanical properties when the annealing temperature was under 500 °.

Hierarchical Design and Nanomechanics of the Calcified Byssus of Anomia simplex

MRS Proceedings ◽

10.1557/proc-1187-kk05-09 ◽

2009 ◽

Vol 1187 ◽

Cited By ~ 2

Author(s):

Jakob R Eltzholtz ◽

Marie Krogsgaard ◽

Henrik Birkedal

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Mechanical Performance ◽

Blue Mussel ◽

Hierarchical Design ◽

Reduced Modulus ◽

Different Types ◽

Microscopy Images ◽

AbstractBiology has evolved several strategies for attachment of sedentary animals. In the bivalves, byssi abound and the best known example being the protein-based byssus of the blue mussel and other Mytilidae. In contrast the bivalve Anomia sp. has a single calcified thread. The byssus is hierarchical in design and contains several different types of structures as revealed by scanning electron microscopy images. The mechanical properties of the byssus are probed by nanoindentation. It is found that the mineralized part of the byssus is very stiff with a reduced modulus of about 67 GPa and a hardness of ˜3.7 GPa. This corresponds to a modulus roughly 20% smaller than that of pure calcite and a hardness that is about 20% larger than pure calcite. The results reveal the importance of microstructure on mechanical performance.