Properties Of Conventional Materials Research Articles

Electric and magnetic metal-insulator-metal metasurfaces in the mid-infrared based on Babinet’s, Lorentz’s, and Kirchhoff’s principles

Metasurfaces can extend the optical properties of conventional materials by structuring surfaces at a subwavelength scale. These artificial subwavelength surfaces mimic the physics of conventional materials and can, in principle, be designed to provide novel optical material properties. Metal-insulator-metal (MIM) antenna metasurfaces are among the most widely used as ideal absorbers and emitters. In this work, we present MIM metasurfaces in the mid-infrared that comply in the electric and magnetic forms of Babinet’s, Lorentz’s, and Kirchhoff’s principles. To verify the validity of Babinet's, Lorentz's, and Kirchhoff's MIM metasurfaces, we computed their reflection and absorption spectra as well as electric and magnetic field maps. We found that even in the presence of graphene on top of the electric and magnetic MIM metasurfaces, these principles still hold qualitatively. However, the excitation of gap surface plasmon polaritons (SPPs) and graphene SPPs fails to comply quantitatively. Additionally, we fabricated the MIM metasurfaces and used imaging Fourier transform infrared spectroscopy in the mid infrared spectrum to validate them. Finally, we explore the potentials and limits of the use of graphene as tunability material, with a tunability bandwidth up to 0.6 µm. Our findings can be applied to the development of electric and magnetic frequency selectivity metasurfaces, polarizers, coherent thermal sources, and detectors.

The effect of nanocarbon inclusion on mechanical, tribological, and thermal properties of phenolic resin‐based composites: An overview

AbstractNanocarbons including carbon nanotubes, graphene oxide, reduced graphene oxide and particularly graphene have unique properties such as high mechanical strength, thermally stable, highly conducting, high friction stability and lower specific wear rates, which can potentially provide synergically improved performance of advanced engineering materials and technologies for various fields of applications such as automotive, aerospace, and other industrial components. Development of phenolic resin‐based nanocomposites comprised of nanocarbon material remained as a research focus to outperform different properties of conventional material based components. In application, phenolic resin is the most popular binder in frictional components development such as brake pads, brake linings, and clutch facings, particularly used in many of light and medium automotive brake pad applications. Specifically, the present review study aims to provide thorough discussion on the mechanical, tribological, and thermal performances of phenolic resin‐based nanocomposites containing nanocarbon as a property modifier by comparing with the neat phenolic resin or with the composite containing other micro ingredients. As per presented overview, the analysis shows the significant improvement in some required application‐based properties of phenolic resin‐based nanocomposites such as tensile strength, young's modulus, impact strength, specific wear rate reduction, residue yield, and thermal conductivity due to the inclusion of nanocarbon, where the content of nanocarbons ranges about 0.5 wt% to 5 wt%. Hence nanocomposites synthesized using phenolic resin matrix with nanocarbons fillers found to have better mechanical strength, better wear resistance, and thermal stabilities when compared to pure phenolic resin and other composites.

Study on the physical, mechanical and mineralogical properties of dredged marine sand as a partial replacement for fine aggregate in concrete

Dredged Marine sand are the excess sediment deposits removed periodically from the beds of artificially constructed ports and harbors to maintain the design depth and to facilitate waterway. Due to this phenomenon, large quantum of dredged marine sand pile near the estuary by routine dredging activities which has initiated several environmental and public issues. To alleviate the issues, in the recent, several studies have been conducted for the effective utilization of dredged marine sand as construction material. Moreover, the dredged marine sand sediments have considerable economic and environmental advantages when employed as a substitute material for natural fine aggregates in concrete production. This study emphasis on the physical, mechanical and mineralogical characteristics of concrete replaced with dredged marine sand as fine aggregate. For the study, the dredged marine sand samples were collected from the dredging site of the Ariyankuppam estuary close to the artificially created fishing harbor of the Puducherry coast. The collected samples were used in concrete after screening with preliminary treatment to remove shells, organic substances, and other contaminants. The investigation conducted on the mineralogical properties of dredged marine sand showed that silicon oxides (quartz), calcite (CaCo3), calcium sulfate (CaSo4), sodium sulfate (Na2So4), and other minerals were present. The presence of calcite, calcium improves the durability and strength of the concrete while, silicon oxides acts as a filler material. The dredged marine sand's physical characteristics indicated that the samples are finer and matches with the properties of conventional materials. The chemical characteristics evidenced the presence of heavy metals like iron (Fe), lead (Pb), and zinc (Zn), which are found in chemical properties, serve to accelerate the reaction in concrete and improve its qualities. For a comparative study, both treated and untreated dredged marine sand partially and completely replaced with M−sand were used in concrete for the investigation. From the analysis of the test results pertaining to the mechanical properties of dredged marine sand concrete which performed better than conventional concrete, a cost-effective way to improve the characteristics of concrete both at its fresh and hardened state.

Analysis of mechanical properties enhancement on composites of AA7175 by multi walled carbon nano tube (MWCNT)

Developed to meet the demands of appealing contemporary materials, nanocomposites are polyphase materials that include a matrix and nano-reinforcement. The major types of nanocomposites are as follows. They are categorized as fiber-reinforced nanocomposites, laminar nanocomposites, and particulate nanocomposites based on the reinforcing component, whereas they are classed as metal matrix, ceramic matrix, and polymer matrix nanocomposites based on the matrix ingredient. Due to its advantages over polymer and ceramic matrix, metal matrix nanocomposites (MMNCs) are the most common type of nanocomposites employed in industrial applications. To improve the physical, mechanical, thermal, and electrical properties of conventional materials, nanocomposites are often formed by reinforcing nanoscale tubes, fibres, particles, or sheets. To keep up with technological advancements, drive market changes, and bridge technological gaps by revolutionizing the product, innovative nanocomposites must be used in advanced engineering applications. The high-strength, light-weight aluminium alloy matrix nanocomposites (AMNCs) are able to replace traditional materials to a greater extent in cutting-edge applications including the automotive, aircraft, marine, defense, leisure, and electronic industries. In this study deals with the property enhancement analysis by means of the assistance of Multi Walled Carbon nano tube (MWCNT) nano particles encouragement in AA7175 aluminium alloy. The main focus of this investigation on the tensile related mechanical properties such as tensile strength, percentage of elongation and yield strength. The composites were created with the mass fractions of 5.0 wt%, 4.0 wt%, 3.0 wt%, 2.0 wt% and 1.0 wt% of MWCNT with 95.0 wt%, 96.0 wt%, 97.0 wt%, 98.0 wt% and 99.0 wt% of AA7175 aluminium alloy. These composite mechanical properties were compared with the pure AA7175 aluminium alloy. Among the comparison of these composites values 3.0 wt% of MWCNT produce the greater results on the considered composites. The composite sample recorded high Ultimate Tensile Strength of 431.12 MPa, low Percentage of elongation of 9.58% and high Yield strength of 396.63 MPa.

Manufacturing of Ti–Nb–Cr–V–Ni high entropy alloy using directed energy deposition and evaluation of materials properties

High entropy alloy (HEA) is a new material that can overcome the limitations of the physical properties of conventional materials, exhibit excellent mechanical properties, and be employed in various extreme environments. In particular, refractory HEA composed of refractory materials such as Ti and Ni are expected to exhibit desirable high-temperature properties. Metal additive manufacturing has a shorter manufacturing time than the conventional casting method and is suitable for HEA manufacturing using various metal materials. Specifically, directed energy deposition (DED) has a high solidification rate that is advantageous for grain refining, prevents intermetallic compounds, and averts shrinkage that occurs in the casting method, thereby reducing cracks and deformations and resulting in fewer defects and superior production quality. In this study, a HEA with desirable high-temperature characteristics that are composed of Ti–Nb–Cr–V–Ni was designed by optimizing thermodynamic parameters and deposited using DED. The deposited Ti–Nb–Cr–V–Ni exhibited a body-centered cubic structure. Tensile strength, hardness, differential scanning calorimetry (DSC), and thermal conductivity analyses were performed to analyze its mechanical and thermal properties. Ti–Nb–Cr–V–Ni exhibited a fine structure and high tensile strength at high temperatures due to the characteristics of the DED process, but low elongation at room temperature. These strength characteristics are attributed to the microstructure of Ti–Nb–Cr–V–Ni, which mainly forms the BCC phase. And Ti–Nb–Cr–V–Ni exhibited high hardness and high thermal stability enough to be used in extreme environments with high temperatures.

Chitosan as an Outstanding Polysaccharide Improving Health-Commodities of Humans and Environmental Protection.

Public health, production and preservation of food, development of environmentally friendly (cosmeto-)textiles and plastics, synthesis processes using green technology, and improvement of water quality, among other domains, can be controlled with the help of chitosan. It has been demonstrated that this biopolymer exhibits advantageous properties, such as biocompatibility, biodegradability, antimicrobial effect, mucoadhesive properties, film-forming capacity, elicitor of plant defenses, coagulant-flocculant ability, synergistic effect and adjuvant along with other substances and materials. In part, its versatility is attributed to the presence of ionizable and reactive primary amino groups that provide strong chemical interactions with small inorganic and organic substances, macromolecules, ions, and cell membranes/walls. Hence, chitosan has been used either to create new materials or to modify the properties of conventional materials applied on an industrial scale. Considering the relevance of strategic topics around the world, this review integrates recent studies and key background information constructed by different researchers designing chitosan-based materials with potential applications in the aforementioned concerns.

From silica colloidal particles to photonic crystals: Progress in fabrication and application of structurally colored materials

Photonic crystals have attracted extensive attention because of their wide application in optics and photonics. These structures can be made by “top-down” or “bottom-up” self-assembly methods. Self-assembly methods have received particular attention due to their low cost, simple manufacturing process, relatively easy scaling, and ease of creating complex structures with nanometer precision. Self-assembled colloidal crystals play an essential role in the formation of photonic crystals. In this article, the assembly of colloidal crystals-silica particles, the synthesis of silica particles, and the assembly of three-dimensional photonic crystals based on inorganic/inorganic and inorganic/organic composites are introduced in detail. The formation of silica based bionic structure material can produce different optical properties of conventional materials. It provides unprecedented opportunities for textiles, pigments, sensing, information encryption, stealth materials, anti-counterfeit marks, energy collection, environmental remediation, and a variety of other application fields.

Semi-circular bending setup for predicting fracture characteristics of high-strength fiber-reinforced concrete

Semi-Circular Bending (SCB) Setup is commonly used to investigate the fracture parameters of the road materials like asphalt mixtures. This paper examines the performance of the SCB setup in extracting the fracture characteristics of high-strength fiber-reinforced concrete (HSFRC). Monofilament and fibrillated polypropylene fibers with polyolefin coatings of 19, 30, and 50 mm length were added to a high-strength concrete mixture at three volume percentages of 0.5, 1, and 1.5 %. Standard cube and cylinder specimens were initially fabricated for conventional material properties tests. Subsequently, the three-point bending test specimens, i.e., intact rectangular beam, notched beam, and SCB, were made using the same concrete mix of different fibers lengths and percentages. A total of 36 beam and SCB tests with three replications was conducted to find the fracture energy and pick load of each specimen. Results showed that selecting the shortest fibers (19 mm) of 0.5 % and 1.5 % by volume increased the elastic modulus and the splitting tensile strength by 70.5 % and 43 %, respectively. Also, increasing the fiber length and volume enhanced the fracture energy of the notched beam and SCB specimens up to 90 times and 40 times, respectively. However, increasing the volume of the fibers was more effective than using longer fibers in fracture energy increase. For these three test setups, finite element models were generated and analyzed to develop a numerical framework capable of predicting the fracture characteristics of HSFRCs with acceptable accuracy (maximum error of 4 %). The concrete damaged plasticity (CDP) model in ABAQUS software package were adopted to simulate the damage initiation and progression in concrete using the material properties from the conventional tests. Comparing the results of beam setups with SCB tests, it was found that SCB can be a reliable and economical setup to find the fracture characteristics of the HSFRCs.

3-D Metamaterials: Trends on Applied Designs, Computational Methods and Fabrication Techniques

Metamaterials are artificially engineered devices that go beyond the properties of conventional materials in nature. Metamaterials allow for the creation of negative refractive indexes; light trapping with epsilon-near-zero compounds; bandgap selection; superconductivity phenomena; non-Hermitian responses; and more generally, manipulation of the propagation of electromagnetic and acoustic waves. In the past, low computational resources and the lack of proper manufacturing techniques have limited attention towards 1-D and 2-D metamaterials. However, the true potential of metamaterials is ultimately reached in 3-D configurations, when the degrees of freedom associated with the propagating direction are fully exploited in design. This is expected to lead to a new era in the field of metamaterials, from which future high-speed and low-latency communication networks can benefit. Here, a comprehensive overview of the past, present, and future trends related to 3-D metamaterial devices is presented, focusing on efficient computational methods, innovative designs, and functional manufacturing techniques.

Effect of solid lubricant addition in coating produced by laser cladding process: A review

This present review article discusses about the effect of solid lubricant additive in surface composite coating deposited by laser cladding and alloying process. Wear and friction is challenging problem in moving machinery parts subjected to rubbing action or sliding motion. Therefore to reduce the wear and friction of sliding machinery parts, coated layer is deposited on the surface of machine component to prevent from surface damage due to wear. Laser cladding and alloying is advanced manufacturing technology by which hard and wear resistant coating material is deposited on the surface of soft conventional materials by use of high power laser energy as heat source to provide good metallurgical adherence between coating and substrate materials. The coating materials generally used for enhancing the friction and wear resistance properties of conventional materials are advanced ceramics, advanced composites, nanomaterials and advanced alloys like high entropy alloys. When solid lubricants are added to these coating materials in limited amount then the friction and wear properties of developed surface improves. The solid lubricant additive in coating materials can reduce the friction coefficient and wear rate of materials. The solid lubricant materials acts as anti-friction and anti-wear agent in the coating materials. The most commonly used solid lubricants are h-BN, CaF2, MoS2, WS2, BaF2 and graphite. In this article the effect of these solid lubricant material on wear resistance and friction coefficient of coated surfaces produced by laser alloying and cladding techniques are described. The various engineering materials used for manufacturing of moving or sliding parts are ferrous materials, titanium alloys, aluminium alloys, magnesium alloys and copper alloys. In this article the coating deposited on these materials with solid lubricant additives by laser cladding and alloying process are reviewed. The problem arises during developing solid lubricant additive coating and its remedies are described.

N-Type thermoelectric properties of a hexagonal SiGe polymorph superior to a cubic SiGe

The crystal structure of a material dictates many of its properties. This study focuses on a SiGe compound with a hexagonal crystal system that demonstrates superior thermoelectric properties than that of its conventional cubic polymorph. Using first-principles density functional theory (DFT) calculations combined with the semi-classical Boltzmann transport equation (BTE), we clearly elucidate the underlying mechanisms that cause the enhanced thermoelectric performance. The hexagonal SiGe compound shows different folding behavior of the electronic band structure, leading to dissimilar density of states and enhanced Seebeck coefficient, compared to the cubic counterpart. Moreover, the phonon vibrational modes of the hexagonal SiGe shorten the phonon lifetime due to the different lattice symmetry. Based on the results, we propose hexagonal SiGe as a promising material for a highly active n-type thermoelectric material with a figure of merit that is twice of its cubic analogue. Our approach demonstrates an attractive method for substantially enhancing conventional material properties without a complicated or expensive process for developing a novel material.

Critical review on porous material manufacturing techniques, properties & their applications

Generally, porosity is not a desirable characteristic of any material. In today’s Industrial scenario, this parameter becomes necessity of materials for different applications like structural, solar absorbers, and sound absorption as well as biomedical applications. Metal foams are cellular structures contain porosity which increases mechanical, thermal and other physical properties of conventional materials. There are manufacturing issues concern with these materials like homogeneity and location of pores, controlling of parameters. In this article, the techniques of manufacturing of porous materials are discussed with their limiting parameters and pros & cons. Powder metallurgy is found suitable for better porosity but the cost for this process constrain its usage among the researchers and Industry as well. Space holder method is one of the found appropriate among all other used for the manufacturing of open and closed cell foam in perspective of cost as well porosity. The orientation of space holder plays a crucial role for the development of better porous object. This article reviews the different methods of manufacturing and their properties for the better future perspective in terms of cost, structure and application of porous foams.

Dome-Patterned Metamaterial Sheets.

The properties of conventional materials result from the arrangement of and the interaction between atoms at the nanoscale. Metamaterials have shifted this paradigm by offering property control through structural design at the mesoscale, thus broadening the design space beyond the limits of traditional materials. A family of mechanical metamaterials consisting of soft sheets featuring a patterned array of reconfigurable bistable domes is reported here. The domes in this metamaterial architecture can be reversibly inverted at the local scale to generate programmable multistable shapes and tunable mechanical responses at the global scale. By 3D printing a robotic gripper with energy‐storing skin and a structure that can memorize and compute spatially‐distributed mechanical signals, it is shown that these metamaterials are an attractive platform for novel mechanologic concepts and open new design opportunities for structures used in robotics, architecture, and biomedical applications.

Selective Modification of Hierarchical Pores and Surfaces in Nanoporous Materials

AbstractTailor‐made ordered mesoporous materials bear great potential in numerous fields of application where large interfaces are required. However, the inherent surfacechemical properties of conventional materials, such as silica, carbon or organosilica, poses some limitations with respect to their application. Surface manipulation by functionalization with chemically more reactive groups is one way to improve materials for their desired purpose. Another approach is the design of high surface‐area composite materials. The surface manipulation, either by functionalization or by introducing guest species, can be performed selectively. This means that when several distinct, i.e. , hierarchical, types of surfaces or pore systems exist in a material, each of them may be chosen for manipulation. Several strategies can be identified to achieve this goal. Molecules or molecule assemblies can be utilized to temporarily protect pores or surfaces (soft protection), while manipulation occurs at the accessible sites. This approach is a recurring motive in this review and can also be applied to rigid template matrices (hard protection). Furthermore, the size of functionalization agents (size protection) and their reactivity/diffusion (kinetic protection) into the pores can also be utilized to achieve selectivity. In addition, challenges in the synthesis and characterization of selectively manipulated ordered mesoporous materials are discussed.

Fatigue crack growth material parameters- based on prototype pipe bend test and comparison with conventional parameters

An experimental study has been performed on a representative prototype-sized pipe bend made of SS 316 LN material to generate the relevant material parameters required for fatigue crack growth (FCG) simulation. Traditionally, FCG numerical simulation material parameters are generated based on specimen level test. In the literature there are many prototype pipe bend test results can be found. However, this paper takes a new look for generating FCG material parameters based on prototype-sized pipe bend test results.A semi-elliptical shaped pre-cracked pipe bend is used for the crack growth studies. Advancement of the crack profile has been measured in a periodic interval of cyclic testing, and the essential crack dimensions are derived to extract the FCG material parameters. FCG response curve derived, based on the prototype sized pipe bend test result, is well below the similar response curve obtained from the conventional material properties. The major reason behind this difference in FCG response is attributed to the influence of the residual stress locked during pipe bend fabrication. Based on these findings, it is recommended to adopt the material parameters derived based on the component-level test for more accurate prediction. Further studies are required to generalise the role of fabrication assisted effects in the material parameters in the case of prototype sized components.

Fiber reinforced metal matrix composites - a review

Modern technology has placed increasing demands on materials. The need of hour is to develop the new materials so as to overcome the limitations of the materials existed presently regarding applications in different fields. The materials with properties such as better wear resistance, high specific strength and stability at high temperatures have been in great demand in the past few decades. The properties of conventional materials can be improved by the method of reinforcing whiskers, fibers and particles in to polymers, metals and ceramics. This has resulted in the manufacturing of composite materials. The mechanical properties of fiber reinforced metal matrix composites (MMCs) make them the suitable choice for applications in the fields of automotive and aerospace etc. The paper outlines the overview of fiber reinforced MMCs. The applications, manufacturing methods and mechanical properties of these composites are discussed. Furthermore, this review describes the single fiber push-out test which is developed in the past years so as to measure quantitatively the properties of the interface between the fiber and the matrix in these fiber reinforced MMCs.

The Effect of Addition of Powder Areca Nut Midrib on Polyester Matrix to the Tensile and Bending Strength

In this life, humans certainly need a variety of equipment called material. In its development the material continues to experience progress as in early life, humans only use equipment made from simple materials such as wood, stone and others. Then move to the metal and the last to use a lot of mixture in the refinement of these materials, one form of mixed material created by humans is composite. Betel nut has a lot of powder, how to take it without damaging the areca nut plant. After the extraction of powder is applied to the areca nut, the fiber will be mixed with polyester resin as its matrix. Polyester resin is a matrix of composites. This resin is also included in thermoset resin. In the thermoset polyester the liquid resin is converted into hard and brittle solids formed by chemical cross-bonds that form very strong polymer chains. The mixture will produce composite materials which have different mechanical properties and characteristics from the forming material. Composite materials have the properties of conventional materials from the manufacturing process through inhomogeneous mixing. The purpose of this study was to determine the effect of adding areca nut powder to the polyester matrix on tensile and bending strength. Research and testing are carried out in several stages, including the manufacture of specimens. Both materials are stirred manually until both materials are fused evenly, then tensile and bending tests are carried out, data analysis and conclusions. The results of this research got the best tensile test values on composite polyester resin specimens and areca nut powder with a composition of 90%: 10% with a value of 5.09 MPa. And the results of bending which got the best bending test values are polyester resin composites and nutmeg powder with a composition of 90%: 10% with bending test values of 3.77MPa.

Recent advances in the understanding of high-kdielectric materials deposited by atomic layer deposition for dynamic random-access memory capacitor applications

Abstract

Mechanisms of Resistance to Silver Nanoparticles in Endodontic Bacteria: A Literature Review

In recent years, the use and research in nanomaterials have increased considerably. In dentistry, nanomaterials have been investigated in all their specialties like dental prosthesis, implantology, dental operative, periodontics, and endodontics. The nanomaterials are investigated in the areas of dentistry due to their application in the improvement of the physical and chemical properties of conventional materials, as well as the use of the antimicrobial activity of nanomaterials such as silver nanoparticles. Recently, silver nanoparticles (AgNPs) have been studied for their use as an endodontic irrigator due to their high antimicrobial activity. But little is known about the possible mechanisms of the adaptation to AgNPs by endodontic bacteria. These mechanisms may be intrinsic (such as efflux pumps, downregulation of porins, and chromosomal resistance genes) or extrinsic (such as point and adaptive mutations and plasmids with resistance genes) adaptation systems. In addition to this, it has been reported that coselection or coregulation of metal resistance mechanisms, as in the case of nanoparticles, is accompanied by increased resistance to various antibiotics. For these reasons, the objective of this article is to do a review of the literature on the possible mechanisms used by endodontic bacteria to generate resistance to silver nanoparticles and the possible side effects of these mechanisms.

Liquid Phase Separation in High-Entropy Alloys-A Review.

It has been 14 years since the discovery of the high-entropy alloys (HEAs), an idea of alloying which has reinvigorated materials scientists to explore unconventional alloy compositions and multicomponent alloy systems. Many authors have referred to these alloys as multi-principal element alloys (MPEAs) or complex concentrated alloys (CCAs) in order to place less restrictions on what constitutes an HEA. Regardless of classification, the research is rooted in the exploration of structure-properties and processing relations in these multicomponent alloys with the aim to surpass the physical properties of conventional materials. More recent studies show that some of these alloys undergo liquid phase separation, a phenomenon largely dictated by low entropy of mixing and positive mixing enthalpy. Studies posit that positive mixing enthalpy of the binary and ternary components contribute substantially to the formation of liquid miscibility gaps. The objective of this review is to bring forth and summarize the findings of the experiments which detail liquid phase separation (LPS) in HEAs, MPEAs, and CCAs and to draw parallels between HEAs and the conventional alloy systems which undergo liquid-liquid separation. Positive mixing enthalpy if not compensated by the entropy of mixing will lead to liquid phase separation. It appears that Co, Ni, and Ti promote miscibility in HEAs/CCAs/MPEAs while Cr, V, and Nb will raise the miscibility gap temperature and increase LPS. Moreover, addition of appropriate amounts of Ni to CoCrCu eliminates immiscibility, such as in cases of dendritically solidifying CoCrCuNi, CoCrCuFeNi, and CoCrCuMnNi.