In‐situ microscopic analysis of ferritic ductile iron during tensile loading: Relation between matrix heterogeneities and damage mechanisms

The in-situ damage progression in three carbon fibre reinforced cross-ply composite systems under tensile loading is examined, namely, carbon IM7/epoxy, carbon IM7/PEEK and carbon AS4/polyamide. Epoxy is a thermoset polymer while polyether ether ketone (PEEK) and polyamide are thermoplastic. The thermoset composite is manufactured in an autoclave using matrix pre-impregnated with unidirectional carbon fibres, while the thermoplastic composites are manufactured using laser-assisted automated tape placement (LATP). A tensile microtester is mounted in a scanning electron microscope to observe the damage mechanisms in-situ under tensile loading. X-ray computed tomography scans are also carried out to examine porosity in the material systems. IM7/epoxy and IM7/PEEK displayed similar damage mechanisms: transverse cracking in 90° plies followed by fibre breakage in the 0° plies at the fillets and interlaminar fracture. AS4/polyamide displayed a different mechanism with fibre fracture appearing first in the 0° plies, followed by transverse cracking and interlaminar fracture. The effect of autoclave treatment on the materials manufactured by LATP has also been examined.

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Molecular and Microscopic Analysis of Altered Gene Expression in Transgenic and Gene Targeted Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100162521 ◽

1996 ◽

Vol 54 ◽

pp. 12-13

Author(s):

W. K. Jones ◽

J. Robbins

Keyword(s):

Gene Expression ◽

Pulmonary Veins ◽

Microscopic Analysis ◽

Mouse Tissue ◽

Adult Heart ◽

Heavy Chains ◽

Altered Gene Expression ◽

Altered Gene ◽

Pulmonary Myocardium

Two myosin heavy chains (MyHC) are expressed in the mammalian heart and are differentially regulated during development. In the mouse, the α-MyHC is expressed constitutively in the atrium. At birth, the β-MyHC is downregulated and replaced by the α-MyHC, which is the sole cardiac MyHC isoform in the adult heart. We have employed transgenic and gene-targeting methodologies to study the regulation of cardiac MyHC gene expression and the functional and developmental consequences of altered α-MyHC expression in the mouse.We previously characterized an α-MyHC promoter capable of driving tissue-specific and developmentally correct expression of a CAT (chloramphenicol acetyltransferase) marker in the mouse. Tissue surveys detected a small amount of CAT activity in the lung (Fig. 1a). The results of in situ hybridization analyses indicated that the pattern of CAT transcript in the adult heart (Fig. 1b, top panel) is the same as that of α-MyHC (Fig. 1b, lower panel). The α-MyHC gene is expressed in a layer of cardiac muscle (pulmonary myocardium) associated with the pulmonary veins (Fig. 1c). These studies extend our understanding of α-MyHC expression and delimit a third cardiac compartment.

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{10-12} Twinning Mechanism During In Situ Micro-Tensile Loading of Pure Mg: Role of Basal Slip and Twin-Twin Boundary Interaction

SSRN Electronic Journal ◽

10.2139/ssrn.3628969 ◽

2020 ◽

Author(s):

Nicolò Maria della Ventura ◽

Szilvia Kalácska ◽

Daniele Casari ◽

Thomas Edward James Edwards ◽

Johann Michler ◽

...

Keyword(s):

Twin Boundary ◽

Basal Slip ◽

Tensile Loading ◽

Boundary Interaction

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Bayesian analysis reveals the impact of load partitioning on microstructural evolution in Ti-6Al-4V during in-situ tensile loading

Materialia ◽

10.1016/j.mtla.2020.100993 ◽

2021 ◽

Vol 15 ◽

pp. 100993

Author(s):

N. Armstrong ◽

P.A. Lynch ◽

P. Cizek ◽

S.R. Kada ◽

S. Slater ◽

...

Keyword(s):

Bayesian Analysis ◽

Microstructural Evolution ◽

Tensile Loading ◽

The Impact

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Damage mechanisms and energy absorption of aluminosilicate glass under compression/tensile loading

Construction and Building Materials ◽

10.1016/j.conbuildmat.2021.123088 ◽

2021 ◽

Vol 288 ◽

pp. 123088

Author(s):

Muhammad Zakir Sheikh ◽

Muhammad Atif ◽

Yulong Li ◽

Fenghua Zhou ◽

Muhammad Aamir Raza ◽

...

Keyword(s):

Energy Absorption ◽

Tensile Loading ◽

Aluminosilicate Glass ◽

Damage Mechanisms

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Fatigue Damage of Al/SiC Composites - Macroscopic and Microscopic Analysis

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0016 ◽

2015 ◽

Vol 60 (1) ◽

pp. 101-105 ◽

Cited By ~ 2

Author(s):

A. Rutecka ◽

Z.L. Kowalewski ◽

K. Makowska ◽

K. Pietrzak ◽

L. Dietrich

Keyword(s):

Fatigue Damage ◽

Microscopic Analysis ◽

Inelastic Strain ◽

Damage Parameter ◽

Fatigue Tests ◽

Cyclic Plasticity ◽

Damage Mechanisms ◽

Before And After ◽

Fatigue Damage Parameter ◽

Sic Composites

Abstract The results of comparative examinations of mechanical behaviour during fatigue loads and microstructure assessment before and after fatigue tests were presented. Composites of aluminium matrix and SiC reinforcement manufactured using the KoBo method were investigated. The combinations of two kinds of fatigue damage mechanisms were observed. The first one governed by cyclic plasticity and related to inelastic strain amplitude changes and the second one expressed in a form of ratcheting based on changes in mean inelastic strain. The higher SiC content the less influence of the fatigue damage mechanisms on material behaviour was observed. Attempts have been made to evaluate an appropriate fatigue damage parameter. However, it still needs further improvements.

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Research on In Situ Anionic Polymerization of PA6/PI Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.21 ◽

2011 ◽

Vol 295-297 ◽

pp. 21-25

Author(s):

Hong Kai Zhao ◽

Li Guang Xiao ◽

Hong Jie Wang

Keyword(s):

Molecular Weight ◽

Bisphenol A ◽

High Performance ◽

Hot Spot ◽

Microscopic Analysis ◽

Infrared Analysis ◽

Elongation At Break ◽

System Temperature ◽

Lamellar Crystals

High performance trend of plastics has become a hot spot of current research. Select bisphenol A dianhydride and bisphenol A diamine with excellent water resistance as the reactant monomers to obtain anhydride-terminated polyimide with very high molecular weight by two-step polymerization, graft the active radicals of acyl caprolactam using the activity of anhydride and obtain PI modified nylon resin by polymerization.When the system temperature is above 160 °C and the added modifiers are greater than 10%, the system viscosity increases very fast; when the system temperature reaches 140 °C and the added modifiers are at 5%, the system viscosity increases very slowly. It is proved that the reaction in each above step is successful through infrared analysis. The mechanical properties of modified PI nylon increases with the increase of consumption and molecular weight of polyimide, when the molecular weight is selected to be about 8000~10000 and the adding amount is 10wt%~15 wt%, the tensile strength reaches over 85MPa, the notch impact strength is increased to 19.6kJ.m-2 and the elongation at break reaches 18%, which are remarkably better than general engineering plastics.Through microscopic analysis, the molecules of polyimide does not enter crystallization phase of nylon resin, but forms compact lamellar crystals existing in nylon matrix.

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In situ microscopic analysis of asbestos and synthetic vitreous fibers retained in hamster lungs following inhalation.

Environmental Health Perspectives ◽

10.1289/ehp.99107367 ◽

1999 ◽

Vol 107 (5) ◽

pp. 367-375 ◽

Cited By ~ 1

Author(s):

R A Rogers ◽

J M Antonini ◽

H Brismar ◽

J Lai ◽

T W Hesterberg ◽

...

Keyword(s):

Microscopic Analysis

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Effect of Hydrogen Peroxide at 35% on the Morphology of Enamel and Interference in the De-remineralization Process: An In Situ Study

Operative Dentistry ◽

10.2341/11-112-l ◽

2012 ◽

Vol 37 (5) ◽

pp. 518-525 ◽

Cited By ~ 15

Author(s):

AM de Arruda ◽

PH dos Santos ◽

RH Sundfeld ◽

SB Berger ◽

ALF Briso

Keyword(s):

Hydrogen Peroxide ◽

Dental Caries ◽

Microscopic Analysis ◽

Enamel Surface ◽

In Situ Study ◽

Bovine Enamel ◽

Histologic Changes

SUMMARY This study evaluated the microhardness and histomorphology of bovine enamel when 35% hydrogen peroxide is used. A total of 44 specimens were adapted to removable devices used by 11 individuals subjected to dental caries challenge. A decrease in microhardness was observed for all groups after the cariogenic challenge. Microscopic analysis revealed that fragments subjected to cariogenic challenge associated with bleaching had more intense superficial histologic changes, but the depth of the lesions remained unchanged. It was concluded that 35% hydrogen peroxide enhanced the reduction in hardness and histomorphologic changes in the enamel surface exposed to cariogenic challenge.

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