Size Effect on Mechanical Properties and Mechanical Behavior of Micron-Sized Amorphous Particles

This paper investigates the mechanical behavior of additive manufactured Triply Periodic Minimal Surface (TPMS) structures, such as Gyroid, Schwarz Diamond and Schwarz Primitive. Fused Filament Fabrication (FFF) technique was utilized in order to fabricate lattice structures with different relative densities, at 10%, 20% and 30%, using Polylactic acid (PLA). The test specimens were formed by structural TPMS unit cells and they were tested under quasi-static compression. A finite element analysis (FEA) was performed in order to predict their stress-strain behavior and compare with the experimental results. The results revealed that each architecture influences the mechanical properties of the structure differently depending on the impact of size effect. The structures were designed as sandwich structures (with a top and bottom plate) to avoid significant deterioration of the mechanical behavior, due to the size effect and this was achieved at high relative densities. The Schwarz Diamond structure demonstrated the highest mechanical strength compared with the other architectures, while the Gyroid structure also revealed a similar mechanical performance. In addition, Schwarz Primitive structure showed increased energy absorption especially during plastic deformation. The overall results revealed that the integrity of the mechanical properties of the studied TPMS FFF printed structures deteriorates, as the relative density of the structures decreases.

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MODELISATION DE L'INFLUENCE DU TRAITEMENT THERMIQUE SUR LES PROPRIETES MECANIQUES DES ALLIAGES ALUMINIUM-CUIVRE (Al-Cu)

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v10i2.1334 ◽

2015 ◽

Vol 10 (2) ◽

pp. 2753-2761

Author(s):

Saad El Madani ◽

S. ELHAMZI ◽

A. IBNLFASSI ◽

L. ZERROUK ◽

O. BEN LENDA ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Behavior ◽

Solidification Process ◽

Traitement Thermique ◽

Homogenization Process ◽

Fundamental Reason ◽

Segregation Phenomenon ◽

Proprietes Mecaniques ◽

Cooling Velocity ◽

Copper Effect

In order to master and improve the quality and properties of the final products, the major industrial challenge lies in the possibility of controlling the morphology, size of microstructures that reside within the molded pieces, as well as their defects; this is the fundamental reason according to which we are more and more interested in mastering the growth and germination of such alloys, as well as the developing structures, at the time of solidification process. The modeling reveals as a valuable aid in the mastery of the formation of such heterogeneousness: segregation cells that are incompatible with industrial requirements.Â Â The whole work focuses upon the modeling of the segregation phenomenon of the four hypoeutectic alloys, Al1%Cu, Al2%Cu, Al3%Cu et Al4%Cu, as well as the copper effect upon certain mechanical properties of aluminum. Usually, the microstructure and mechanical behavior of such alloys as Al-Cu are directly influenced by some parameters such as composition, cooling velocity and homogenization process.

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Experimental Study on the Mechanical Properties and Compression Size Effect of Recycled Aggregate Concrete

Materials ◽

10.3390/ma14092323 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2323

Author(s):

Yubing Du ◽

Zhiqing Zhao ◽

Qiang Xiao ◽

Feiting Shi ◽

Jianming Yang ◽

...

Keyword(s):

Mechanical Properties ◽

Size Effect ◽

Compressive Stress ◽

Failure Modes ◽

Recycled Concrete ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Aggregate Concrete ◽

Substitution Ratio ◽

The Impact

To explore the basic mechanical properties and size effects of recycled aggregate concrete (RAC) with different substitution ratios of coarse recycled concrete aggregates (CRCAs) to replace natural coarse aggregates (NCA), the failure modes and mechanical parameters of RAC under different loading conditions including compression, splitting tensile resistance and direct shear were compared and analyzed. The conclusions drawn are as follows: the failure mechanisms of concrete with different substitution ratios of CRCAs are similar; with the increase in substitution ratio, the peak compressive stress and peak tensile stress of RAC decrease gradually, the splitting limit displacement decreases, and the splitting tensile modulus slightly increases; with the increase in the concrete cube’s side length, the peak compressive stress of RAC declines gradually, but the integrity after compression is gradually improved; and the increase in the substitution ratio of the recycled aggregate reduces the impact of the size effect on the peak compressive stress of RAC. Furthermore, an influence equation of the coupling effect of the substitution ratio and size effect on the peak compressive stress of RAC was quantitatively established. The research results are of great significance for the engineering application of RAC and the strength selection of RAC structure design.

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Experimental and Numerical Evaluation of Mechanical Properties of 3D-Printed Stainless Steel 316L Lattice Structures

Journal of Materials Engineering and Performance ◽

10.1007/s11665-021-05737-w ◽

2021 ◽

Author(s):

M. Carraturo ◽

G. Alaimo ◽

S. Marconi ◽

E. Negrello ◽

E. Sgambitterra ◽

...

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Mechanical Behavior ◽

Numerical Simulations ◽

Uniaxial Tensile ◽

Uniaxial Tensile Test ◽

Lattice Structures ◽

Stainless Steel 316L ◽

Research Attention ◽

Octet Truss

AbstractAdditive manufacturing (AM), and in particular selective laser melting (SLM) technology, allows to produce structural components made of lattice structures. These kinds of structures have received a lot of research attention over recent years due to their capacity to generate easy-to-manufacture and lightweight components with enhanced mechanical properties. Despite a large amount of work available in the literature, the prediction of the mechanical behavior of lattice structures is still an open issue for researchers. Numerical simulations can help to better understand the mechanical behavior of such a kind of structure without undergoing long and expensive experimental campaigns. In this work, we compare numerical and experimental results of a uniaxial tensile test for stainless steel 316L octet-truss lattice specimen. Numerical simulations are based on both the nominal as-designed geometry and the as-build geometry obtained through the analysis of µ-CT images. We find that the use of the as-build geometry is fundamental for an accurate prediction of the mechanical behavior of lattice structures.

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Decoupling of Mechanical and Transport Properties in Organogels via Solvent Variation

Gels ◽

10.3390/gels7020061 ◽

2021 ◽

Vol 7 (2) ◽

pp. 61

Author(s):

Kenneth P. Mineart ◽

Cameron Hong ◽

Lucas A. Rankin

Keyword(s):

Mechanical Properties ◽

Mechanical Behavior ◽

Transdermal Drug Delivery ◽

Triblock Copolymer ◽

Polymer Concentration ◽

Mineral Oil ◽

Solute Diffusion ◽

Oil Viscosity ◽

Chain Entanglement ◽

Mineral Oils

Organogels have recently been considered as materials for transdermal drug delivery media, wherein their transport and mechanical properties are among the most important considerations. Transport through organogels has only recently been investigated and findings highlight an inextricable link between gels’ transport and mechanical properties based upon the formulated polymer concentration. Here, organogels composed of styrenic triblock copolymer and different aliphatic mineral oils, each with a unique dynamic viscosity, are characterized in terms of their quasi-static uniaxial mechanical behavior and the internal diffusion of two unique solute penetrants. Mechanical testing results indicate that variation of mineral oil viscosity does not affect gel mechanical behavior. This likely stems from negligible changes in the interactions between mineral oils and the block copolymer, which leads to consistent crosslinked network structure and chain entanglement (at a fixed polymer concentration). Conversely, results from diffusion experiments highlight that two penetrants—oleic acid (OA) and aggregated aerosol-OT (AOT)—diffuse through gels at a rate inversely proportional to mineral oil viscosity. The inverse dependence is theoretically supported by the hydrodynamic model of solute diffusion through gels. Collectively, our results show that organogel solvent variation can be used as a design parameter to tailor solute transport through gels while maintaining fixed mechanical properties.

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Understanding the Barrier and Mechanical Behavior of Different Nanofillers in Chitosan Films for Food Packaging

Polymers ◽

10.3390/polym13050721 ◽

2021 ◽

Vol 13 (5) ◽

pp. 721 ◽

Cited By ~ 1

Author(s):

João Pires ◽

Camila Damásio de Paula ◽

Victor Gomes Lauriano Souza ◽

Ana Luísa Fernando ◽

Isabel Coelhoso

Keyword(s):

Mechanical Properties ◽

Mechanical Behavior ◽

Food Packaging ◽

Scientific Research ◽

Barrier Properties ◽

Plastic Pollution ◽

Functional Attributes ◽

Chitosan Films ◽

Commercial Applications ◽

Innovative Techniques

The continuous petroleum-based plastics manufacturing generates disposal issues, spreading the problem of plastic pollution and its rise in the environment. Recently, innovative techniques and scientific research promoted biopolymers as the primary alternative for traditional plastics, raising and expanding global bioplastic production. Due to its unmatched biological and functional attributes, chitosan (Ch) has been substantially explored and employed as a biopolymeric matrix. Nevertheless, the hydrophilicity and the weak mechanical properties associated with this biopolymer represent a significant intrinsic restriction to its implementation into some commercial applications, namely, in food packaging industries. Distinct methodologies have been utilized to upgrade the mechanical and barrier properties of Ch, such as using organic or inorganic nanofillers, crosslinkers, or blends with other polymers. This review intends to analyze the most recent works that combine the action of different nanoparticle types with Ch films to reinforce their mechanical and barrier properties.

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Microstructure and Mechanical Properties of Ti-6Al-4V Manufactured by SLM

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.651-653.677 ◽

2015 ◽

Vol 651-653 ◽

pp. 677-682 ◽

Cited By ~ 33

Author(s):

Anatoliy Popovich ◽

Vadim Sufiiarov ◽

Evgenii Borisov ◽

Igor Polozov

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Phase Composition ◽

Mechanical Behavior ◽

Ductile Fracture ◽

Elevated Temperatures ◽

Initial Material ◽

Laser Melting ◽

Microstructure And Mechanical Properties ◽

Before And After

The article presents results of a study of phase composition and microstructure of initial material and samples obtained by selective laser melting of titanium-based alloy, as well as samples after heat treatment. The effect of heat treatment on microstructure and mechanical properties of specimens was shown. It was studied mechanical behavior of manufactured specimens before and after heat treatment at room and elevated temperatures as well. The heat treatment allows obtaining sufficient mechanical properties of material at room and elevated temperatures such as increase in ductility of material. The fractography of samples showed that they feature ductile fracture with brittle elements.

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Mechanical behavior of frozen soil improved with sulphoaluminate cement and its microscopic mechanism

Scientific Reports ◽

10.1038/s41598-020-73148-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Zhenhua Yin ◽

Hu Zhang ◽

Jianming Zhang ◽

Mingtang Chai

Keyword(s):

Mechanical Properties ◽

Mechanical Behavior ◽

Soil Improvement ◽

Particle Size Analysis ◽

Frozen Soil ◽

Size Analysis ◽

Permafrost Soil ◽

Compression Tests ◽

Microscopic Mechanism ◽

Sulphoaluminate Cement

Abstract The foundation of constructions built in the permafrost areas undergo considerable creeping or thawing deformation because of the underlying ice-rich permafrost. Soil improvement may be of advantage in treating ice-rich permafrost at shallow depth. Sulphoaluminate cement was a potential material to improve frozen soil. Simultaneously, two other cements, ordinary Portland cement and Magnesium phosphate cement were selected as the comparison. The mechanical behavior of modified frozen soil was studied with thaw compression tests and unconfined compression strength tests. Meanwhile, the microscopic mechanism was explored by field emission scanning electron microscopy, particle size analysis and X-ray diffractometry. The results showed Sulphoaluminate cement was useful in reducing the thaw compression deformation and in enhancing the strength of the frozen soil. The improvement of the mechanical behavior depended mainly on two aspects: the formation of structural mineral crystals and the agglomeration of soil particles. The two main factors contributed to the improvement of mechanical properties simultaneously. The thicker AFt crystals result in a higher strength and AFt plays an important role in improving the mechanical properties of frozen soils.The study verified that Sulphoaluminate cement was an excellent stabilizer to improve ice-rich frozen soils.

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MICROSTRUCTURE AND MECHANICAL BEHAVIOR OF AMORPHOUS Al–Cu–Ti METAL FOAMS SYNTHESIZED BY SPARK PLASMA SINTERING

Surface Review and Letters ◽

10.1142/s0218625x18500221 ◽

2017 ◽

Vol 24 (Supp02) ◽

pp. 1850022

Author(s):

MAOYUAN LI ◽

LIN LU ◽

ZHEN DAI ◽

YIQIANG HONG ◽

WEIWEI CHEN ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Behavior ◽

Intermetallic Compounds ◽

Spark Plasma Sintering ◽

Elevated Temperatures ◽

Volume Fraction ◽

Metal Foams ◽

Plasma Sintering ◽

Spark Plasma ◽

Xrd Patterns

Amorphous Al–Cu–Ti metal foams were prepared by spark plasma sintering (SPS) process with the diameter of 10[Formula: see text]mm. The SPS process was conducted at the pressure of 200 and 300[Formula: see text]MPa with the temperature of 653–723[Formula: see text]K, respectively. NaCl was used as the space-holder, forming almost separated pores with the porosity of 65 vol%. The microstructure and mechanical behavior of the amorphous Al–Cu–Ti metal foams were systematically investigated. The results show that the crystallinity increased at elevated temperatures. The effect of pressure and holding time on the crystallization was almost negligible. The intermetallic compounds, i.e. Al–Ti, Al–Cu and Al–Cu–Ti were identified from X-ray diffraction (XRD) patterns. It was found that weak adhesion and brittle intermetallic compounds reduced the mechanical properties, while lower volume fraction and smaller size of NaCl powders improved the mechanical properties.

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A Zebrafish Embryo Behaves both as a “Cortical Shell – Liquid Core” Structure and a Homogeneous Solid when Experiencing Mechanical Forces

Microscopy and Microanalysis ◽

10.1017/s1431927614013269 ◽

2014 ◽

Vol 20 (6) ◽

pp. 1841-1847 ◽

Cited By ~ 1

Author(s):

Fei Liu ◽

Dan Wu ◽

Ken Chen

Keyword(s):

Mechanical Properties ◽

Mechanical Behavior ◽

Zebrafish Embryo ◽

Large Strain ◽

Liquid Core ◽

Small Strain ◽

Core Structure ◽

Mechanical Forces ◽

Cortical Shell ◽

A Cell

AbstractMechanical properties are vital for living cells, and various models have been developed to study the mechanical behavior of cells. However, there is debate regarding whether a cell behaves more similarly to a “cortical shell – liquid core” structure (membrane-like) or a homogeneous solid (cytoskeleton-like) when experiencing stress by mechanical forces. Unlike most experimental methods, which concern the small-strain deformation of a cell, we focused on the mechanical behavior of a cell undergoing small to large strain by conducting microinjection experiments on zebrafish embryo cells. The power law with order of 1.5 between the injection force and the injection distance indicates that the cell behaves as a homogenous solid at small-strain deformation. The linear relation between the rupture force and the microinjector radius suggests that the embryo behaves as membrane-like when subjected to large-strain deformation. We also discuss the possible reasons causing the debate by analyzing the mechanical properties of F-actin filaments.

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