Faculty Opinions recommendation of Large-scale mechanical properties of Xenopus embryonic epithelium.

Nowadays, rapid prototyping is an emerging trend that is followed by industries and auto sector on a large scale which produces intricate geometrical shapes for industrial applications. The wire arc additive manufacturing (WAAM) technique produces large scale industrial products which having intricate geometrical shapes, which is fabricated by layer by layer metal deposition. In this paper, the CMT technique is used to fabricate single-walled WAAM samples. CMT has a high deposition rate, lower thermal heat input and high cladding efficiency characteristics. Humping is a common defect encountered in the WAAM method which not only deteriorates the bead geometry/weld aesthetics but also limits the positional capability in the process. Humping defect also plays a vital role in the reduction of hardness and tensile strength of the fabricated WAAM sample. The humping defect can be controlled by using low heat input parameters which ultimately improves the mechanical properties of WAAM samples. Two types of path planning directions namely uni-directional and bi-directional are adopted in this paper. Results show that the optimum WAAM sample can be achieved by adopting a bi-directional strategy and operating with lower heat input process parameters. This avoids both material wastage and humping defect of the fabricated samples.

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Carbon dots embedded nanofiber films: Large-scale fabrication and enhanced mechanical properties

Chinese Chemical Letters ◽

10.1016/j.cclet.2021.06.073 ◽

2021 ◽

Author(s):

Chang Liu ◽

Rui Cheng ◽

Jiazhuang Guo ◽

Ge Li ◽

He Li ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Dots ◽

Large Scale

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Investigating the effect of different shielding gas mixtures on microstructure and mechanical properties of 410 stainless steel fabricated via large scale additive manufacturing

Additive Manufacturing ◽

10.1016/j.addma.2020.101821 ◽

2020 ◽

pp. 101821

Author(s):

Sougata Roy ◽

Bishal Silwal ◽

Andrzej Nycz ◽

Mark Noakes ◽

Ercan Cakmak ◽

...

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Additive Manufacturing ◽

Large Scale ◽

Gas Mixtures ◽

Shielding Gas ◽

Microstructure And Mechanical Properties

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Polyamide 12/Multiwalled Carbon Nanotube and Carbon Black Nanocomposites Manufactured by 3D Printing Fused Filament Fabrication: A Comparison of the Electrical, Thermoelectric, and Mechanical Properties

C – Journal of Carbon Research ◽

10.3390/c7020038 ◽

2021 ◽

Vol 7 (2) ◽

pp. 38

Author(s):

Nectarios Vidakis ◽

Markos Petousis ◽

Lazaros Tzounis ◽

Emmanuel Velidakis ◽

Nikolaos Mountakis ◽

...

Keyword(s):

Mechanical Properties ◽

3D Printing ◽

Carbon Black ◽

Large Scale ◽

Fracture Mechanisms ◽

Fused Filament Fabrication ◽

Melt Mixing ◽

Multiwalled Carbon ◽

Electrically Conductive ◽

Polyamide 12

In this study, nanocomposites with polyamide 12 (PA12) as the polymer matrix and multiwalled carbon nanotubes (MWCNTs) and carbon black (CB) at different loadings (2.5, 5.0, and 10.0 wt.%) as fillers, were produced in 3D printing filament form by melt mixing extrusion process. The filament was then used to build specimens with the fused filament fabrication (FFF) three-dimensional (3D) printing process. The aim was to produce by FFF 3D printing, electrically conductive and thermoelectric functional specimens with enhanced mechanical properties. All nanocomposites’ samples were electrically conductive at filler loadings above the electrical percolation threshold. The highest thermoelectric performance was obtained for the PA12/CNT nanocomposite at 10.0 wt.%. The static tensile and flexural mechanical properties, as well as the Charpy’s impact and Vickers microhardness, were determined. The highest improvement in mechanical properties was observed for the PA12/CNT nanocomposites at 5.0 wt.% filler loading. The fracture mechanisms were identified by fractographic analyses of scanning electron microscopy (SEM) images acquired from fractured surfaces of tensile tested specimens. The nanocomposites produced could find a variety of applications such as; 3D-printed organic thermoelectric materials for plausible large-scale thermal energy harvesting applications, resistors for flexible circuitry, and piezoresistive sensors for strain sensing.

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Mechanical Properties of Protective Coatings against Marine Fouling: A Review

Polymers ◽

10.3390/polym13020173 ◽

2021 ◽

Vol 13 (2) ◽

pp. 173

Author(s):

Alessandro Pistone ◽

Cristina Scolaro ◽

Annamaria Visco

Keyword(s):

Mechanical Properties ◽

Large Scale ◽

Protective Coatings ◽

Scale Up ◽

Product Distribution ◽

Properties Of Coatings ◽

Fouling Organism ◽

Ship Hulls ◽

Marine Industry ◽

Application Fields

The accumulation of marine organisms on ship hulls, such as microorganisms, barnacles, and seaweeds, represents a global problem for maritime industries, with both economic and environmental costs. The use of biocide-containing paints poses a serious threat to marine ecosystems, affecting both target and non-target organisms driving science and technology towards non-biocidal solutions based on physico-chemical and materials properties of coatings. The review reports recent development of hydrophobic protective coatings in terms of mechanical properties, correlated with the wet ability features. The attention is focused mainly on coatings based on siloxane and epoxy resin due to the wide application fields of such systems in the marine industry. Polyurethane and other systems have been considered as well. These coatings for anti-fouling applications needs to be both long-term mechanically stable, perfectly adherent with the metallic/composite substrate, and capable to detach/destroy the fouling organism. Prospects should focus on developing even “greener” antifouling coatings solutions. These coatings should also be readily addressable to industrial scale-up for large-scale product distribution, possibly at a reasonable cost.

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Approximate Dynamic Programming Based Control of Proppant Concentration in Hydraulic Fracturing

Mathematics ◽

10.3390/math6080132 ◽

2018 ◽

Vol 6 (8) ◽

pp. 132 ◽

Cited By ~ 17

Author(s):

Harwinder Singh Sidhu ◽

Prashanth Siddhamshetty ◽

Joseph Kwon

Keyword(s):

Mechanical Properties ◽

Dynamic Programming ◽

Hydraulic Fracturing ◽

Young’S Modulus ◽

Large Scale ◽

Approximate Dynamic Programming ◽

Young's Modulus ◽

Computational Cost ◽

Control Technique ◽

Rock Mechanical Properties

Hydraulic fracturing has played a crucial role in enhancing the extraction of oil and gas from deep underground sources. The two main objectives of hydraulic fracturing are to produce fractures with a desired fracture geometry and to achieve the target proppant concentration inside the fracture. Recently, some efforts have been made to accomplish these objectives by the model predictive control (MPC) theory based on the assumption that the rock mechanical properties such as the Young’s modulus are known and spatially homogenous. However, this approach may not be optimal if there is an uncertainty in the rock mechanical properties. Furthermore, the computational requirements associated with the MPC approach to calculate the control moves at each sampling time can be significantly high when the underlying process dynamics is described by a nonlinear large-scale system. To address these issues, the current work proposes an approximate dynamic programming (ADP) based approach for the closed-loop control of hydraulic fracturing to achieve the target proppant concentration at the end of pumping. ADP is a model-based control technique which combines a high-fidelity simulation and function approximator to alleviate the “curse-of-dimensionality” associated with the traditional dynamic programming (DP) approach. A series of simulations results is provided to demonstrate the performance of the ADP-based controller in achieving the target proppant concentration at the end of pumping at a fraction of the computational cost required by MPC while handling the uncertainty in the Young’s modulus of the rock formation.

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Preparation and characterization of acrylic polymer titania hybrid. A study of organicinorganic interactions in hybrid materials by micro-hardness Vickers

MRS Proceedings ◽

10.1557/proc-726-q6.23 ◽

2002 ◽

Vol 726 ◽

Cited By ~ 1

Author(s):

Van Nhan Nguyen ◽

François Xavier Perrin ◽

Jean-Louis Vernet

Keyword(s):

Mechanical Properties ◽

Large Scale ◽

Sol Gel ◽

Mechanical Analysis ◽

Polymer Chains ◽

Segmental Motion ◽

Acrylic Polymer ◽

Titania Content ◽

Mineral Constituent ◽

Free Films

AbstractMetal-oxide ceramer films have been developed using an acrylic polymer bearing a low amount of methacrylic acid units (ca. 4%mol) as the organic phase with titanium tetrabutoxide as the inorganic sol-gel precursor. The characterisation of free films was realized by various experimental methods. The formation of COOTi bonds prevents large scale phase separation between the organic component and the mineral network. Mechanical properties of the hybrid films have been investigated through dynamic mechanical analysis. The influence of the titania content on the damping peak amplitude suggests that titania is molecularly dispersed in the polymer matrix and that it significantly hinders the segmental motion of the polymer chains. However, the low content in potential carboxylic crosslinking sites explains why the glass transition temperature remains relatively unchanged when titania content increases. Vickers microhardness measurements used in this study allowed us to understand the contribution of the inorganic part (phase TiO2) to the mechanical properties of the polymer. The creep of hybrids has been studied carrying out hardness measurements under various indentation times. The mineral constituent leads to an important increase of the hardness and limits, in a significant way, the creep of polymer.

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