Mechanical Characterization of Woven Composites at Different Temperatures.

Polyvinyl alcohol is a biocompatible polymer used very commonly both in pharmaceutical and medical fields. Being a water-soluble polymer, it is suitable for the manufacture of hydrogels as well as cryogels used for various medical applications. The present work describes the preparation, structural and physico-mechanical characterization of polyvinyl alcohol cryogels loaded with ketoprofen. By cryogenic technique the polymeric solutions are transformed under certain conditions into porous, elastic and very compressible structures. They are able to absorb a large amount of liquids that they give off by gentle compression. The prepared cryogels were evaluated for different physical, chemical and structural properties, as following: internal morphology, equilibrium swelling ratio and mechanical testing. The cryogel structures show good elasticity and optimal swelling at different temperatures. Due to these properties the studied cryogels are suitable for use in various medical applications involving liquid absorption, mechanical resistance and anti-inflammatory effect.

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A Contribution to the Mechanical Characterization of Cu ETP Used in the Electric Motors Industry

Materials Science Forum ◽

10.4028/www.scientific.net/msf.730-732.679 ◽

2012 ◽

Vol 730-732 ◽

pp. 679-684

Author(s):

Pedro M.G.P. Moreira ◽

Miguel A.V. de Figueiredo ◽

Paulo M.S.T. de Castro

Keyword(s):

Mechanical Characterization ◽

Base Material ◽

Tensile Tests ◽

Electric Motors ◽

Lower Strength ◽

Before And After ◽

Different Temperatures ◽

Remote Stress ◽

Hardness Values

The analysis of Cu ETP of a component of electric motors manufactured by WEG is presented. The work included three main tasks: metallographic analyses at the micro and macro levels; mechanical testing; scanning electron microscopy observations. The objective was the evaluation of the state of bars material before and after service. It was found that material in both conditions presents similar microstructures. This indicates that, despite the rotor working at temperatures above 300°C, no grain recrystallization can be identified. It was verified that the copper bar base material presents higher hardness values of than the copper ring. A decrease of yield and rupture stresses as the temperature increases was observed during tensile tests at different temperatures. During testing, a fatigue life of 107 cycles for a remote stress of approximately 134MPa is estimated. It can be concluded that the material after and before service presents different properties, the first one presenting lower strength. This behavior is reflected in lower hardness, yield and rupture stress of the material taken from the fractured rotor bars. This observation can be a result of the high temperature (above 300°C) that is present in the rotor during each start.

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Formability Evaluation of Grade 1 Titanium Sheets Depending on the Temperature by FE Analyses

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.651-653.1054 ◽

2015 ◽

Vol 651-653 ◽

pp. 1054-1059 ◽

Cited By ~ 2

Author(s):

Antonio Formisano ◽

Antonello Astarita ◽

Luca Boccarusso ◽

F. Capece Minutolo ◽

Luigi Carrino ◽

...

Keyword(s):

Titanium Alloys ◽

Test Temperature ◽

Weight Reduction ◽

Mechanical Characterization ◽

Incremental Forming ◽

General Knowledge ◽

Phase Information ◽

Flexible Forming ◽

Different Temperatures

Nowadays, the need of developing high flexible forming processes matches with the need of weight reduction. In this light, the incremental forming of titanium alloys sheets can guarantee both these aspects by combining the flexibility of the process, particularly suggested for small batches and customized parts, with the good properties of titanium alloys, in particular for aerospace applications.The aim of this work was to obtain information useful to enhance the general knowledge of the hot incremental forming processes of grade 1 titanium sheets at different temperatures.First, both tensile and straight groove tests were carried out by varying the test temperature; in this phase, information regarding both the forming forces and the wear phenomena due to the tool-sheet contact was acquired.Successively, on the basis of the mechanical characterization of the sheets previously carried out, explicit analyses, effectuated by a non-linear FE code, allowed to determine the formability curves of the sheets for the different temperatures.

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Thermodynamics/hydrodynamics of aqueous polymer solutions and dynamic mechanical characterization of solid films of chitosan, sodium alginate, guar gum, hydroxy ethyl cellulose and hydroxypropyl methylcellulose at different temperatures

Carbohydrate Polymers ◽

10.1016/j.carbpol.2005.11.018 ◽

2006 ◽

Vol 65 (1) ◽

pp. 9-21 ◽

Cited By ~ 28

Author(s):

Venkatesh Mutalik ◽

Lata S. Manjeshwar ◽

Ashwini Wali ◽

Malladi Sairam ◽

K.V.S.N. Raju ◽

...

Keyword(s):

Sodium Alginate ◽

Ethyl Cellulose ◽

Guar Gum ◽

Mechanical Characterization ◽

Hydroxypropyl Methylcellulose ◽

Dynamic Mechanical ◽

Solid Films ◽

Aqueous Polymer ◽

Different Temperatures

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Mechanical characterization of Trebisacce stone: preliminary results

Rendiconti online della Società Geologica Italiana ◽

10.3301/rol.2016.14 ◽

2016 ◽

Vol 38 ◽

pp. 47-50

Author(s):

Giulia Forestieri ◽

Maurizio Ponte

Keyword(s):

Mechanical Characterization ◽

Preliminary Results

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Massively Parallel Mechanical Characterization of Nanowires

10.26226/morressier.5f5f8e69aa777f8ba5bd5f86 ◽

2020 ◽

Author(s):

Rodrigo Bernal

Keyword(s):

Mechanical Characterization ◽

Massively Parallel

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Spectro-mechanical Characterization of Aromaticity and Maturity of Kerogens in Oil Shale at 6 nm Spatial Resolution

10.26434/chemrxiv.7336160 ◽

2018 ◽

Author(s):

Devon Jakob ◽

Le Wang ◽

Haomin Wang ◽

Xiaoji Xu

Keyword(s):

Spatial Resolution ◽

Oil Shale ◽

Infrared Imaging ◽

Mechanical Characterization ◽

Optical Diffraction ◽

Chemical Compositions ◽

Valuable Insight ◽

Eagle Ford Shale

<p>In situ measurements of the chemical compositions and mechanical properties of kerogen help understand the formation, transformation, and utilization of organic matter in the oil shale at the nanoscale. However, the optical diffraction limit prevents attainment of nanoscale resolution using conventional spectroscopy and microscopy. Here, we utilize peak force infrared (PFIR) microscopy for multimodal characterization of kerogen in oil shale. The PFIR provides correlative infrared imaging, mechanical mapping, and broadband infrared spectroscopy capability with 6 nm spatial resolution. We observed nanoscale heterogeneity in the chemical composition, aromaticity, and maturity of the kerogens from oil shales from Eagle Ford shale play in Texas. The kerogen aromaticity positively correlates with the local mechanical moduli of the surrounding inorganic matrix, manifesting the Le Chatelier’s principle. In situ spectro-mechanical characterization of oil shale will yield valuable insight for geochemical and geomechanical modeling on the origin and transformation of kerogen in the oil shale.</p>

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