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Showing 1 to 20 of 20 for “"micromechanisms"”.
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Micromechanisms of paperboard deformation
An experimental study of the micromechanisms of paperboard deformation has been conducted. Experiments were performed in a scanning electron microscope, allowing visual observation and coincident acquisition of load vs. deformation data. Deformation mechanisms were determined and correlated with …
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Micromechanisms of polymer sliding wear
A study has been made concerning the tribological behaviour of ultrahigh molecular weight polyethylene (UHMWPE) during water-lubricated reciprocating sliding wear. The experimental work has been extended to study also the effect of molecular weight, fillers, lubrication, counterface roughness and …
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Characterizing the Three-Dimensional Behavior of Bistable Micromechanisms
Compliant bistable micromechanisms have been proposed for use in applications such as switches, relays, shutters, and sensing arrays. Unpublished laboratory testing suggests that off-axis forces may affect the bistable nature of fully compliant bistable micromechanisms (FCBMs). The actuation forces …
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Crack growth behavior and failure micromechanisms in three heat-resistant materials at elevated temperature
Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:05:13Z Item is restricted indefinitely.
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The low temperature fracture behaviour of the super duplex stainless steel Zeron 100
The micromechanisms of fracture in an austenitic/ferritic super-duplex stainless steel (Zeron 100) have been studied for a range of product forms, including cross-rolled plate, conventional (ingot) route and powder route extruded pipe, hot isostatically pressed (HIP'd) powder, and weldments …
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Development of In-Plane Compliant Bistable Microrelays
… presents three new compliant bistable micromechanisms, and characterizes their performance as microrelays. The characterization includes a treatment of a new force-tester, a preliminary contact resistance study, contact-force measurements, switching time measurements, insertion loss, AC …
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Relationship between Microstructure, Properties and HICC Resistance of HSLA steel weld metals
… and hydrogen content on the fracture micromechanisms. A critical hydrogen content (Ck) was estimated for each weld metal. The trapping capacity 'of each weld metal was studied using an electrochemical double pulse technique to measure the hydrogen trapping constant (k). The weld metals …
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Simulation-Based Design Under Uncertainty for Compliant Microelectromechanical Systems
… and experimentally validated using bistable micromechanisms and thermal microactuators as examples.
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Micromechanics of deformation in polymers modified by inorganic and rubber particles
… element analysis, this thesis examines the micromechanisms of deformation for the toughened polymer blends. Particularly, how the nature of the particles and its bonding with the matrix affect the development of plastic deformation in the matrix material. Micromechanical models are …
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Uncovering the link between twin-twin interactions and damage nucleation in an (α+β) Ti alloy
… and high ductility; however, the plasticity micromechanisms that lead to damage nucleation for this alloy had not yet been investigated in detail. In this work, post-mortem analysis and an in-situ SEM-EBSD tensile experiment were conducted to determine where damage was nucleating most …
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Micromechanistic analysis of fatigue in aluminium silicon casting alloys
… intermetallic sub-structure. As a result, the micromechanisms of fatigue are different to those in conventional particulate Al-Si alloys because particle fracture is required to ensure a level of crack continuity. At room temperature and 350ºC, and at low and high crack growth rates, the crack …
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A gradient-damage theory for quasi brittle fracture
… is the result of microscale decohesion/damage micromechanisms. In this thesis we discuss the formulation of our gradient-damage theory for quasi-brittle fracture using the virtual-power method. The macro- and microforce balances, obtained from the virtual power approach, together with a …
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A Self-Retracting Fully-Compliant Bistable Micromechanism
… of Self-Retracting Fully-compliant Bistable Micromechanisms (SRFBM). Fully-compliant mechanisms are needed to overcome the inherent limitations of microfabricated pin joints, especially in bistable mechanisms. The elimination of the clearances associated with pin joints will allow more …
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Micromechanical modeling of the toughening mechanisms in particle-modified semicrystalline polymers
… study aims to elucidate the micromechanics and micromechanisms responsible for the high toughness exhibited by these morphologically altered heterogeneous material systems via a series of micromechanical models. The case of polyamide-6 modified with spherical elastomeric particles was modeled. …
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Mechanism of subcritical crack growth in the alumina reinforced aluminum-copper composite: Effects of interface and matrix microstructure
Micromechanisms of fracture and fatigue crack growth were examined in an $\rm Al\sb2O\sb3/Al$-Cu composite and its matrix alloy, with particular emphases on effects of matrix and interfacial microstructure. The matrix and interfacial microstructures were controlled by aging the composite to …
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Modeling Microvoid Localization with Explicit Finite Element Analysis
Ductile fracture is characterized by the micromechanisms of void nucleation, growth, and coalescence. Numerical modeling of these micromechanical phenomena has typically been performed with an implicit finite element analysis (FEA) solver, which accurately produces quasi-static results, but …
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Thermal Microactuators for Microelectromechanical Systems (MEMS)
… µm in two directions. Thermomechanical In-plane Micromechanisms (TIMs) were the third group tested. They produced a linear motion up to 20 µm. The fourth group was the Rapid Expansion Bi-directional Actuators (REBAs). These microactuators were bi-directional and produced up to 12 µm deflection in …
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Identification of Macro- and Micro-Compliant Mechanism Configurations Resulting in Bistable Behavior
… been applied to the design of several bistable micromechanisms. In the process of searching for usable designs for micro-bistable mechanisms, a mechanism class was defined, known as "Young" mechanisms, which represent a feasible and useful way of achieving micro-mechanism motion similar to that …
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Mechanical behavior of nonwoven felts
… polypropylene fibers. The deformation and damage micromechanisms of the glass-fiber non-woven felt were analyzed with a combination of experiments and simulations. Tensile tests were carried out on unnotched and notched rectangular panels to ascertain the physical phenomena which control the …
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Micromecánica de elastómeros porosos y reforzados con fibras
… and toughness on the tensile strength and damage micromechanisms. It was found that the onset of damage and tensile strength were controlled by interface strength while the evolution of damage depended on interface toughness.