Viscoelastic behaviour in indium alloys: InSn, InBi, InCd and InSnCd

The viscoelastic penetration and tensile behaviour of poly(methyl acrylate) and poly(ethyl acrylate) in the main transition region have been investigated. It was found that the time-temperature superposition could be carried out in the case of the penetration viscoelastic behaviour; the temperature dependence of the penetration and tensile shift factors was the same. The superimposed curves of the penetration and Young modulus allowed us to calculate the dependence of the Poisson ratio and thus to characterize the change in sample volume with deformation. It was demonstrated that the penetration method of determination of the viscoelastic behaviour is equivalent to the tensile method.

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Evolution of the viscoelastic properties of painting stratigraphies: a moisture weathering and nanoindentation approach

Heritage Science ◽

10.1186/s40494-021-00552-x ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Mathilde Tiennot ◽

Davide Iannuzzi ◽

Erma Hermens

Keyword(s):

Mechanical Properties ◽

Relative Humidity ◽

Cultural Heritage ◽

Mechanical Behaviour ◽

Viscoelastic Properties ◽

Viscoelastic Behaviour ◽

Storage And Loss Moduli ◽

Heritage Studies ◽

Paint Films ◽

The Impact

AbstractIn this investigation on the mechanical behaviour of paint films, we use a new ferrule-top nanoindentation protocol developed for cultural heritage studies to examine the impact of repeated relative humidity variations on the viscoelastic behaviour of paint films and their mechanical properties in different paint stratigraphies through the changes in their storage and loss moduli. We show that the moisture weathering impact on the micromechanics varies for each of these pigment-oil systems. Data from the nanoindentation protocol provide new insights into the evolution of the viscoelastic properties dsue to the impact of moisture weathering on paint films.

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Viscoelastic behaviour of rapid and slow self-healing hydrogels formed by densely branched arabinoxylans from Plantago ovata seed mucilage

Carbohydrate Polymers ◽

10.1016/j.carbpol.2021.118318 ◽

2021 ◽

pp. 118318

Author(s):

Long Yu ◽

Jason R. Stokes ◽

Gleb E. Yakubov

Keyword(s):

Viscoelastic Behaviour ◽

Self Healing ◽

Plantago Ovata ◽

Seed Mucilage

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Distinctive rheological and temporal viscoelastic behaviour of alkali-activated fly ash/slag pastes: A comparative study with cement paste

Cement and Concrete Research ◽

10.1016/j.cemconres.2021.106441 ◽

2021 ◽

Vol 144 ◽

pp. 106441

Author(s):

Mohammed Fouad Alnahhal ◽

Taehwan Kim ◽

Ailar Hajimohammadi

Keyword(s):

Fly Ash ◽

Comparative Study ◽

Cement Paste ◽

Viscoelastic Behaviour ◽

Alkali Activated

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Effect of fibre content on the mechanical properties of hemp fibre woven fabrics/polypropylene composite laminates

Polymers and Polymer Composites ◽

10.1177/09673911211023942 ◽

2021 ◽

pp. 096739112110239

Author(s):

Sheedev Antony ◽

Abel Cherouat ◽

Guillaume Montay

Keyword(s):

Mechanical Properties ◽

Polymer Matrix ◽

Composite Laminates ◽

Volume Fraction ◽

Fibre Volume Fraction ◽

Fibre Volume ◽

Woven Fabrics ◽

Fibre Content ◽

Viscoelastic Behaviour ◽

Hemp Fibre

Nowadays natural fibre composites have gained great significance as reinforcements in polymer matrix composites. Composite material based on a polymer matrix reinforced with natural fibres is extensively used in industry due to their biodegradability, recyclability, low density and high specific properties. A study has been carried out here to investigate the fibre volume fraction effect of hemp fibre woven fabrics/PolyPropylene (PP) composite laminates on the tensile properties and impact hammer impact test. Initially, composite sheets were fabricated by the thermal-compression process with desired number of fabric layers to obtain composite laminates with different fibre volume fraction. Uniaxial, shear and biaxial tensile tests were performed and mechanical properties were calculated. Impact hammer test was also carried out to estimate the frequency and damping parameters of stratified composite plates. Scanning Electron Microscope (SEM) analysis was performed to observe the matrix and fibre constituent defects. Hemp fabrics/PP composite laminates exhibits viscoelastic behaviour and as the fibre volume fraction increases, the viscoelastic behaviour decreases to elastic behaviour. Due to this, the tensile strength increases as the fibre content increases. On the other hand, the natural frequency increases and damping ratio decrease as the fibre volume fraction increases.

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