A New Device for Evaluating Load-Transfer In Geosynthetic Reinforced Soils

Numerous phenomenological descriptions of the mechanical behavior of composite materials have been developed. There is now an urgent need to study and interpret deformation behavior, load transfer, and strain distribution, in terms of micromechanisms at the atomic level. One approach is to characterize dislocation substructure resulting from specific test conditions by the various techniques of transmission electron microscopy. The present paper describes a technique for the preparation of electron transparent composites of aluminum-stainless steel, such that examination of the matrix-fiber (wire), or interfacial region is possible. Dislocation substructures are currently under examination following tensile, compressive, and creep loading. The technique complements and extends the one other study in this area by Hancock.The composite examined was hot-pressed (argon atmosphere) 99.99% aluminum reinforced with 15% volume fraction stainless steel wire (0.006″ dia.).Foils were prepared so that the stainless steel wires run longitudinally in the plane of the specimen i.e. the electron beam is perpendicular to the axes of the wires. The initial step involves cutting slices ∼0.040″ in thickness on a diamond slitting wheel.

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Deformation at interfaces of Ti-6Al-4V/SiC fiber composites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121193 ◽

1992 ◽

Vol 50 (1) ◽

pp. 158-159

Author(s):

Warren J. Moberly ◽

Daniel B. Miracle ◽

S. Krishnamurthy

Keyword(s):

Thermal Stresses ◽

Load Transfer ◽

Coefficient Of Thermal Expansion ◽

Hot Isostatic Pressing ◽

Matrix Composites ◽

Ongoing Research ◽

Aerospace Applications ◽

Sic Fiber ◽

The Matrix ◽

Intermetallic Matrix Composites

Titanium-aluminum alloy metal matrix composites (MMC) and Ti-Al intermetallic matrix composites (IMC), reinforced with continuous SCS6 SiC fibers are leading candidates for high temperature aerospace applications such as the National Aerospace Plane (NASP). The nature of deformation at fiber / matrix interfaces is characterized in this ongoing research. One major concern is the mismatch in coefficient of thermal expansion (CTE) between the Ti-based matrix and the SiC fiber. This can lead to thermal stresses upon cooling down from the temperature incurred during hot isostatic pressing (HIP), which are sufficient to cause yielding in the matrix, and/or lead to fatigue from the thermal cycling that will be incurred during application, A second concern is the load transfer, from fiber to matrix, that is required if/when fiber fracture occurs. In both cases the stresses in the matrix are most severe at the interlace.

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Influence of nocturnal bruxism on the stomatognathic system. Part I: a new device for measuring mandibular movements during sleep

Journal of Oral Rehabilitation ◽

10.1046/j.1365-2842.2001.00757.x ◽

2001 ◽

Vol 28 (10) ◽

pp. 943-949 ◽

Cited By ~ 20

Author(s):

Y. Amemori ◽

S. Yamashita ◽

M. Ai ◽

H. Shinoda ◽

M. Sato ◽

...

Keyword(s):

New Device ◽

Stomatognathic System ◽

System Part ◽

Mandibular Movements

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Histological verification of non-specific aorta-arteritis (Takayasu's arteritis) using percutaneous transluminal atherectomy

VASA ◽

10.1024/0301-1526.33.4.247 ◽

2004 ◽

Vol 33 (4) ◽

pp. 247-251 ◽

Cited By ~ 6

Author(s):

Zeller ◽

Koch ◽

Frank ◽

Bürgelin ◽

Schwarzwälder ◽

...

Keyword(s):

Clinical Diagnosis ◽

Axillary Artery ◽

Takayasu’S Arteritis ◽

Giant Cells ◽

Interventional Therapy ◽

Takayasu's Arteritis ◽

New Device ◽

First Case ◽

Anti Inflammatory ◽

Percutaneous Transluminal

Diagnosis of non-specific aorto-arteritis (NSAA, Takaysu's arteritis) is typically based on clinical and investigational parameters. We report here about two patients with clinically suspected diagnosis of a Takayasu's arteritis already under anti-inflammatory therapy in whom percutaneous transluminal atherectomy of subclavian and axillary artery stenoses was performed to relief the patients from symptoms – intermittent dyspraxia of the arms – and to verify the clinical diagnosis by histology. In the first case aorto-arteritis could be histologically confirmed through the analysis of plaque material including media structures excised from the subclavian and axillary arteries using a new device for atherectomy. The biopsy showed diffuse inflammation and granulomatous lesions with giant cells typically for Takayasu's disease. In the second patient, biopsy showed no acute or chronic inflammatory signs but only atherosclerotic lesions. Percutaneous transluminal atherectomy is therefore not only an interventional but also a diagnostic tool and should be used in every case of interventional therapy of suspected aorto-arteritis to make the clinical diagnosis and as a major consequence the initiation of an aggressive anti-inflammatory medical therapy more reliable.

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