Influence of the Microstructure on the Fracture Behavior of Carbon Bonded Alumina

2013 ◽  
Vol 592-593 ◽  
pp. 279-282 ◽  
Author(s):  
Stefan Soltysiak ◽  
Martin Abendroth ◽  
Meinhard Kuna ◽  
Steffen Dudczig
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Fracture Behavior ◽  
Small Punch Test ◽  
Open Cell ◽  
Small Punch ◽  
Punch Test ◽  
Different Types ◽  
Scanning Electron

Carbon bonded alumina (Al2O3-C) in various compositions are developed for the production of open cell filters, which are used for melt metal filtration processes [. The Small Punch Test (SPT) is used to determine the mechanical properties of such materials. Previous investigations showed two different types of fracture behavior [2,, which can be distinguished by typical features of the load deflection curves of the SPT. This paper clarifies this behavior by examining the fracture surfaces using scanning electron microscopy (SEM).

Hierarchical Design and Nanomechanics of the Calcified Byssus of Anomia simplex

2009 ◽  
Vol 1187 ◽  
Author(s):  
Jakob R Eltzholtz ◽  
Marie Krogsgaard ◽  
Henrik Birkedal
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Mechanical Performance ◽  
Blue Mussel ◽  
Hierarchical Design ◽  
Reduced Modulus ◽  
Different Types ◽  
Microscopy Images ◽  
Scanning Electron

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.

Evaluation of 4330M Steel for Fasteners Applications

2017 ◽  
Vol 380 ◽  
pp. 198-211 ◽  
Author(s):  
A. Al Sumait ◽  
C. Delgado ◽  
F. Aldhabib ◽  
X. Sun ◽  
F. Alzubi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Tensile Testing ◽  
Grain Structure ◽  
Hardness Testing ◽  
Heat Treated ◽  
Different Types ◽  
Strength And Ductility ◽  
Scanning Electron

The objective of the study was to optimize the strength and ductility values of the 4330M steel. Optimization was conducted through different types of heat treatments. Tensile testing, hardness testing, optical microscopy, and Scanning Electron Microscopy (SEM) were used to evaluate the mechanical properties and microstructure of the as-received and the heat treated samples. The alloy was provided from two vendors; vendor H and vendor S. Results showed that by increasing the tempering temperatures, strength values decreases, while ductility values remain unchanged. Vendor H samples had higher strength values and much finer grain structure which was revealed only at 5000x magnification.

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

1982 ◽  
Vol 40 ◽  
pp. 680-681
Author(s):  
Li Li-Sheng ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
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.

Scanning electron microscopy of asbestos-containing material where the asbestos fibers are considered locked in a binder

1993 ◽  
Vol 51 ◽  
pp. 472-473
Author(s):  
J. R. Millette ◽  
R. S. Brown
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Environmental Protection Agency ◽  
Building Materials ◽  
The United States ◽  
Protection Agency ◽  
Asbestos Fibers ◽  
Different Types ◽  
Binder Material ◽  
Scanning Electron

The United States Environmental Protection Agency (EPA) has labeled as “friable” those building materials that are likely to readily release fibers. Friable materials when dry, can easily be crumbled, pulverized, or reduced to powder using hand pressure. Other asbestos containing building materials (ACBM) where the asbestos fibers are in a matrix of cement or bituminous or resinous binders are considered non-friable. However, when subjected to sanding, grinding, cutting or other forms of abrasion, these non-friable materials are to be treated as friable asbestos material. There has been a hypothesis that all raw asbestos fibers are encapsulated in solvents and binders and are not released as individual fibers if the material is cut or abraded. Examination of a number of different types of non-friable materials under the SEM show that after cutting or abrasion, tuffs or bundles of fibers are evident on the surfaces of the materials. When these tuffs or bundles are examined, they are shown to contain asbestos fibers which are free from binder material. These free fibers may be released into the air upon further cutting or abrasion.

scholarly journals Microstructural Analysis of Fractured Orthopedic Implants

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2209
Author(s):  
Mateusz Kopec ◽  
Adam Brodecki ◽  
Grzegorz Szczęsny ◽  
Zbigniew L. Kowalewski
Keyword(s):  
Physical Activity ◽  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Fracture Behavior ◽  
Locking Plate ◽  
Microstructural Analysis ◽  
Pure Titanium ◽  
Orthopedic Implants ◽  
Mechanical Loads ◽  
Scanning Electron

In this paper, fracture behavior of four types of implants with different geometries (pure titanium locking plate, pure titanium femoral implant, Ti-6Al-4V titanium alloy pelvic implant, X2CrNiMo18 14-3 steel femoral implant) was studied in detail. Each implant fractured in the human body. The scanning electron microscopy (SEM) was used to determine the potential cause of implants fracture. It was found that the implants fracture mainly occurred in consequence of mechanical overloads resulting from repetitive, prohibited excessive limb loads or singular, un-intendent, secondary injures. Among many possible loading types, the implants were subjected to an excessive fatigue loads with additional interactions caused by screws that were mounted in their threaded holes. The results of this work enable to conclude that the design of orthopedic implants is not fully sufficient to transduce mechanical loads acting over them due to an increasing weight of treated patients and much higher their physical activity.

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

Polymers ◽  
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 ◽  
Scanning Electron Microscopy ◽  
Tensile Strength ◽  
Glassy State ◽  
Nanofibrillated Cellulose ◽  
Dynamic Mechanical Properties ◽  
Initial Modulus ◽  
Surface Modified ◽  
Scanning Electron

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.

scholarly journals Corrosion Behavior and Mechanical Properties of a Nanocomposite Superhydrophobic Coating

Coatings ◽  
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 ◽  
Scanning Electron Microscopy ◽  
Atomic Force Microscopy ◽  
Nanocomposite Coating ◽  
Superhydrophobic Coating ◽  
Force Microscopy ◽  
Atomic Force ◽  
Microscopy Images ◽  
Scanning Electron

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.

scholarly journals Unraveling the fine-tuned lemon coloration of a pierid butterfly Catopsilia pomona

Microscopy ◽  
2017 ◽  
Vol 66 (6) ◽  
pp. 414-423
Author(s):  
Monalisa Mishra ◽  
Ashutosh Choudhury ◽  
P Sagar Achary ◽  
Harekrushna Sahoo
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Variable Temperature ◽  
Wing Pattern ◽  
Physical Composition ◽  
Different Types ◽  
Microscopy Techniques ◽  
Pierid Butterfly ◽  
Best Fit ◽  
Scanning Electron

Abstract Butterflies wings possess different types of scales to perform diverse functions. Each scale has many nano and microstructures, which interferes with light, resulting in unique coloration for each butterfly. Besides coloration, the arrangement of scales further helps in giving better survivability. Thus, analysis of wing pattern provides an overall idea about adaptation and activity of the animal. The current study deciphers the structure and composition of a wing of a pierid butterfly Catopsilia pomona, which remains active at 42°C at which temperature all other butterflies face a tougher task for existence. In order to know the relation between survivability and adaptation in the wing, we have investigated the structural and physical composition of the wing of C. pomona under optical spectroscopy (absorption, reflectance and transmittance) along with microscopy techniques (optical and scanning electron microscopy), which are not described in earlier studies. The current findings reveal unique structural arrangement within scales to provide the best fit to the animal in variable temperature.

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

2021 ◽  
pp. 095400832110055
Author(s):  
Yang Wang ◽  
Yuhui Zhang ◽  
Yuhan Xu ◽  
Xiucai Liu ◽  
Weihong Guo
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Differential Scanning Calorimetry ◽  
Crystallization Behavior ◽  
High Impact ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Scanning Electron

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.

Application of Small Punch Test to Evaluate Tensile Properties of SA213T22 Grade Boiler Steel

2015 ◽  
Vol 830-831 ◽  
pp. 191-194
Author(s):  
M. Venkateswara Rao
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Tensile Properties ◽  
Test Methods ◽  
Uniaxial Tensile ◽  
Test Results ◽  
Small Punch Test ◽  
Small Punch ◽  
Punch Test ◽  
Aging Phenomena

Conventional tensile test methods are used for service exposed high temperature boiler tubes to evaluate the deterioration in mechanical properties such as tensile strength, yield strength and percentage elongation. The mechanical properties are required to be evaluated periodically as the boiler components undergo material degradation due to aging phenomena. The aging phenomena occurs due to continuous exposure of tubes to high temperature & pressure steam prevailing inside the tubes and high temperature exposure to corrosive combustible gases from the external surfaces within the boiler.A recent developed new technique called small punch testing has been used to evaluate the tensile properties of SA 213T22 grade steel predominantly exists in super-heater and re-heater sections of boiler. The small punch tests have been carried out on the miniature disk shaped specimens of diameter of 8.0 mm and 0.5 mm thickness extracted from both the new and service exposed tubes. Conventional uniaxial tensile tests on standard specimens from the same tube material have also been performed for comparison. The service exposed tubes showed considerable loss in mechanical properties in both the conventional and small punch test results. Correlations of tensile properties have been obtained based on the comparative analysis of both small punch and uniaxial tensile test results. Further, the study showed that an appropriate empirical relation could be generated for new and service exposed materials between both the techniques. Conventional test methods require large quantity of material removal for test samples from in-service components whereas small punch test method needs only a miniature sample extraction. This small punch test technique could also be extended to evaluate the thicker section boiler components such as pipelines and headers in the boiler as a part of remaining life assessment study. Also this technique could be a useful tool to any metallic component where large quantity of sample removal may be difficult or may not be feasible.

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