Material Characterization of Pin-Core Latex Polymer Foam Under Static and Dynamic Loads

In this paper, the performance of a PDMS-based microfluidic device is thoroughly characterized for detecting continuous static and dynamic loads. This device comprises of a single PDMS rectangular microstructure and a set of electrolyte-enabled distributed transducers. It is fabricated by a standard fabrication process well developed for PDMS-based microfluidic devices. One potential application of this device is to measure spatially-varying mechanical properties of heterogeneous soft materials, through quasi-static, stress relaxation and dynamic mechanical analysis (DMA) tests. Thus, the response of this device to three types of inputs: static, step and sinusoidal, is examined with a custom experimental setup. For the first time, the capability of using a polymer-based microfluidic device to detect sinusoidal inputs is reported. The characterized results demonstrate the potential of using this device to measure soft materials.

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Correlation of Global Quantities at Material Characterization of Pressure-Sensitive Materials Using Sharp Indentation Testing

Lubricants ◽

10.3390/lubricants9030029 ◽

2021 ◽

Vol 9 (3) ◽

pp. 29

Author(s):

Carl F. O. Dahlberg ◽

Jonas Faleskog ◽

Per-Lennart Larsson

Keyword(s):

Finite Element ◽

Material Characterization ◽

Pressure Sensitivity ◽

Pressure Sensitive ◽

The Mean ◽

Sharp Indentation ◽

Von Mises ◽

Von Mises Plasticity ◽

Hardness Values

Correlation of sharp indentation problems is examined theoretically and numerically. The analysis focuses on elastic-plastic pressure-sensitive materials and especially the case when the local plastic zone is so large that elastic effects on the mean contact pressure will be small or negligible as is the case for engineering metals and alloys. The results from the theoretical analysis indicate that the effect from pressure-sensitivity and plastic strain-hardening are separable at correlation of hardness values. This is confirmed using finite element methods and closed-form formulas are presented representing a pressure-sensitive counterpart to the Tabor formula at von Mises plasticity. The situation for the relative contact area is more complicated as also discussed.

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Material characterization of curved shells under finite deformation using the virtual fields method

Strain ◽

10.1111/str.12398 ◽

2021 ◽

Author(s):

Pieter Livens ◽

Stéphane Avril ◽

Joris J. J. Dirckx

Keyword(s):

Finite Deformation ◽

Material Characterization ◽

Virtual Fields Method

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Experimental investigation on material characterization of zirconia reinforced Alumina ceramic composites via powder forming process

10.1063/5.0024964 ◽

2020 ◽

Author(s):

T. Sathish ◽

S. Arunkumar ◽

R. Saravanan ◽

V. Dhinakaran

Keyword(s):

Experimental Investigation ◽

Material Characterization ◽

Ceramic Composites ◽

Alumina Ceramic ◽

Forming Process ◽

Powder Forming

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New Research on the Use of Hardening Plastics for Aircraft Construction

Journal of the Royal Aeronautical Society ◽

10.1017/s0368393100104961 ◽

1940 ◽

Vol 44 (349) ◽

pp. 44-73

Author(s):

Wilhelm Kuech

Keyword(s):

Strength Properties ◽

Dynamic Loads ◽

Absorbed Energy ◽

Good Strength ◽

Different Temperatures ◽

Bonding Properties ◽

Static And Dynamic Loads ◽

Impact Bending ◽

New Research ◽

Laminated Materials

Laminated materials incorporating plastics seem to be especially well suited lor highly stressed aircraft components, by reason of their good strength properties. Paper, fabric and wood veneers treated with plastics on a phenolic basis were tested with regard to their strength, especially in bending, shear, absorbed energy in impact bending, notching strength and in their resistance against moisture. Further, the behaviour of compressed plastics was studied at different temperatures under static and dynamic loads. A part of the research was extended to pure phenol resin and to thermoplastics based on methacrylate and polyvinylchloride. The bonding properties of laminated compressed plastics were established. Concluding, some experiments relating to the practical manufacture of aeroplane components are communicated.

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Preliminary investigation of use of flexible folding wing tips for static and dynamic load alleviation

The Aeronautical Journal ◽

10.1017/aer.2016.108 ◽

2016 ◽

Vol 121 (1235) ◽

pp. 73-94 ◽

Cited By ~ 19

Author(s):

A. Castrichini ◽

V. Hodigere Siddaramaiah ◽

D.E. Calderon ◽

J.E. Cooper ◽

T. Wilson ◽

...

Keyword(s):

Aspect Ratio ◽

Preliminary Investigation ◽

Aircraft Design ◽

Dynamic Loads ◽

Induced Drag ◽

Aeroelastic Model ◽

Static And Dynamic Loads ◽

Folding Wing ◽

Wing Tips ◽

Wing Tip

ABSTRACTA recent consideration in aircraft design is the use of folding wing-tips with the aim of enabling higher aspect ratio aircraft with less induced drag while also meeting airport gate limitations. This study investigates the effect of exploiting folding wing-tips in flight as a device to reduce both static and dynamic loads. A representative civil jet aircraft aeroelastic model was used to explore the effect of introducing a wing-tip device, connected to the wings with an elastic hinge, on the load behaviour. For the dynamic cases, vertical discrete gusts and continuous turbulence were considered. The effects of hinge orientation, stiffness, damping and wing-tip weight on the static and dynamic response were investigated. It was found that significant reductions in both the static and dynamic loads were possible. For the case considered, a 25% increase in span using folding wing-tips resulted in almost no increase in loads.

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