Material Selection Strategies Research Articles

Identifying the animal species used to manufacture bone arrowheads in South Africa

The identification to species of completely worked bone tools is impossible using standard skeletal morphological markers. Worked bone studies therefore have focused on questions about manufacture and use, rather than on issues of raw material selection strategies. Zooarchaeology by Mass Spectrometry (ZooMS) is a technique that uses unique collagen biomarkers to fingerprint and identify species of origin from small amounts of bone or ivory. We present the first ZooMS analysis of bone arrowheads from southern Africa. Our findings show that a narrower selection of species was selected for tool manufacture than for food, while, at some sites, certain antelope species were selected for tools that are not present in the unmodified faunal remains. We examine what this selectivity might suggest about mechanical suitability and symbolic associations of the species chosen to make tools. We conclude that mechanical suitability was probably of primary concern and that probable symbolic connotations that were attached to certain species did not translate to the technological sphere to the same extent that they did in other parts of the world.

A framework for sustainable nanomaterial selection and design based on performance, hazard, and economic considerations

Engineered nanomaterials (ENMs) and ENM-enabled products have emerged as potentially high-performance replacements to conventional materials and chemicals. As such, there is an urgent need to incorporate environmental and human health objectives into ENM selection and design processes. Here, an adapted framework based on the Ashby material selection strategy is presented as an enhanced selection and design process, which includes functional performance as well as environmental and human health considerations. The utility of this framework is demonstrated through two case studies, the design and selection of antimicrobial substances and conductive polymers, including ENMs, ENM-enabled products and their alternatives. Further, these case studies consider both the comparative efficacy and impacts at two scales: (i) a broad scale, where chemical/material classes are readily compared for primary decision-making, and (ii) within a chemical/material class, where physicochemical properties are manipulated to tailor the desired performance and environmental impact profile. Development and implementation of this framework can inform decision-making for the implementation of ENMs to facilitate promising applications and prevent unintended consequences.

Materials Selection of Optimized Titanium Alloys for Aircraft Applications

The aim of the present work was to explore the correlation between the physical metallurgy of titanium alloys and its main attributes to select optimized materials for structural aircraft applications in the landing gear beam. The Ashby's method was employed as the materials selection strategy to consolidate and evaluate the data collected from the current literature in a comprehensive and consistent analysis. Landing gear beam materials are mainly β and near-β alloys. Considering the need for high specific strength and fatigue resistance, the best candidate among them was Ti-3.5Al-5Mo-6V-3Cr-2Sn-0.5Fe alloy. Finally, a brief discussion of additional aspects related to alloy design, microstructural features and their influence on the mechanical properties is presented.

Analysis and Improvement of Material Selection for Process Piping System in Offshore Industry

Material failure mainly because of corrosion is a highly dangerous and expensive phenomenon in the offshore sector of the oil and gas industry, associated with severe negative consequences such as loss of asset, loss of production due to plant shutdown, loss of human life, and health, safety, and environment (HSE) problems (e.g. environmental pollution). Additionally, piping systems are produced in large numbers for the topside facilities in the oil and gas plants. Thus, the main aim of this paper is to introduce a novel approach for the piping material selection in the offshore industry to minimize the risk of piping corrosion and weight reduction with an optimum cost. The central focus of the study is to develop a material selection tool based on a systematic material selection approach and the existing literature, standards, and specifications. In this study, the optimal material selection strategy includes three well-known methods of screening: Cambridge material selector, value engineering (VE), and technique for order preference by similarity to ideal solution (TOPSIS). The proposed guideline is a practical reference for material and piping engineers in the offshore industry to select the best choice of material for a specific application. The main finding of this research is that 25% chromium super duplex stainless steel is the best choice of material for processing piping systems in offshore plants for non-sour process (hydrocarbon) services. Super duplex stainless steel provides a high corrosion resistance and mechanical strength with the advantage of weight reduction for the selected facilities. A method of piping cost analysis is introduced to validate super duplex stainless steel as the most economical option.

Recent Developments in Mild Steel Corrosion Rate Predictive Models in Sweet Environments

An accurate and reliable corrosion rate prediction is an essential parameter in design, material selection, and mitigation strategies for oil and gas transmission pipelines. While underestimating the corrosion rates may result in health, safety, environmental concerns and financial loss due to maintenance costs and production interruption, overestimation of this parameter may result in significant unnecessary costs for pipeline construction and maintenance. Such concerns have been a strong driving force for developing a better understanding of the corrosion phenomena and advancements in the corrosion rate predictive tools. The corrosion rate predictive models developed to date can be classified depending on the mathematical description of the fundamental thermodynamics and kinetic processes, underlying the corrosion phenomena. That includes empirical models, semi-empirical models, elementary mechanistic models, and comprehensive mechanistic models. The advantages and deficiencies of each group of models was discussed in detail in an earlier review [1]. The present study is focused on improving the comprehensive mechanistic models. Considering the importance of the chemical composition of the solution, the water speciation calculations were updated with more recent literature data. The non-ideal behavior of the gas phase (CO2) in terms of fugacity coefficient and the liquid phase in terms of activity coefficients were incorporated into the model. It was shown that assuming an ideal behavior would result in significant error in chemical speciation at pCO2>10 bar. A more simple charge transfer rate calculations were proposed to replace the Tafel equation commonly used in the literature. It is shown that not only these expressions are mathematically more simple, but they are also more theoretically consistent with the conditions typical in corroding systems. The effect of organic acids (acetic acid in particular) is included in the CO2 corrosion model considering the recent mechanistic findings [2]. The existing comprehensive mathematical models usually assume an infinitely diluted solution in calculations. This matter is also disused in terms of the effect of non-ideal solutions in mass transfer and charge transfer rates. The present model was developed based on moderately diluted solution theory to partially accommodate for the non-ideal behavior but maintain a reasonable computation time. Furthermore, the precipitation and growth of an iron carbonate corrosion product layer is included in the model to account for the effect of this protective layer on the mass transfer and charge transfer rates.

Environmental change and raw material selection strategies at Taoshan: a terminal Late Pleistocene to Holocene site in north‐eastern China

ABSTRACTThe Lesser Khingan Mountains of north‐eastern China are heavily forested, making archaeological site identification difficult owing to poor ground surface visibility. Nevertheless, several prehistoric archaeological site discoveries have been made in recent years and a limited number of excavations have been initiated. One of the most important sites to emerge is Taoshan, which has yielded stratified stone tool assemblages dating from the Last Glacial Maximum (LGM) to the mid‐Holocene. Pollen profiles indicate significant changes in vegetation, fluctuating from steppe conditions during the LGM to forested conditions in the Bølling–Allerød interstadial (B–A) and the mid‐Holocene. The stone tool assemblages from Taoshan were primarily produced from varieties of volcanic tuff, rhyolite, hornfels and agate. Geological prospecting and petrological analyses were performed to document procurement sources and changes in raw material exploitation strategies. During the LGM, the predominant raw material was vitric tuff, available from a source ca. 5–10 km from Taoshan. In the B–A and mid‐Holocene layers, emphasis was on the exploitation of raw materials in gravel bars, although stone tool reduction techniques and raw material preferences changed considerably during this time interval. Diachronic changes in raw materials and exploitation strategies correspond to changes in vegetation and human adaptations.

Design and Research on English Listening Teaching Assisted by Computer Multimedia

this paper mainly introduces the theoretical basis, principle and design theory of listening teaching of foreign language assisted with computer multimedia, analyzes the demand of English listening teaching assisted by computer multimedia in one school, collects and analyzes questionnaire carefully and understand the situation of English listening teaching in this school. Explore the practice of English listening teaching assisted by computer multimedia in one school, relating to material selection and teaching strategy of English listening teaching, at the same time; analyze the practice results of English listening teaching assisted by computer multimedia in this school. Sort out and analyze the collected data, attain the results of this exploration and propose suggestions for problems existed in English listening teaching assisted by computer multimedia.

Integrated product-process design to suggest appropriate manufacturing technology: a review

The materials and manufacturing processes are evolving very rapidly subject to today’s high performance, shorter lead times, and high part complexity needs. With over 80,000 materials, various manufacturing technologies (additive and traditional), diverse streams of application (aerospace, motor vehicles, health care, etc.), and high cost incurred due to manufacturability of the part, it has become essential to choose the right compromise of technology resource in early stages of design considering the Design for Manufacturing (DFM)/Design for Additive Manufacturing (DFAM) guidelines. The concerned literature to date focuses on manufacturing technology selection by being either part specific or application specific. As multiple criteria are involved for decision making, this paper provides a thorough review on the following questions: (1) What are the common design criteria used in literature for additive and traditional manufacturing technologies with respect to product-process integration? (2) What is the literature contribution for material and manufacturing process selection strategies with special focus on comparison of additive and traditional manufacturing technologies? The paper attempts to provide as a result a basic generic methodology for resource selection (RS) which will not only take into account all of the areas of application, DFM/DFAM guidelines, and three design criteria (function, cost, and environment), but will also discuss avenues for collaborative product development. A complex industrial case study is also presented to test the proposed methodology.

Innovative viscoelastic material selection strategy based on dma and mini-shaker tests for spacecraft applications

With the increase of payload sensitivity (such as high precision optics for sub-metric imager), micro-vibration disturbances generated by spinning actuators, if not controlled, may affect on-board instruments and may worsen the quality of pictures taken by an Earth observation imager. For the last two decades, viscoelastic materials have been gradually used in isolators designed for space applications. Their attractiveness comes from their ability to act as a second order low pass filter to minimise micro-vibration forces. In this study, an innovative viscoelastic material pre-selection process has been developed to assess the mechanical and thermal properties of viscoelastic isolators during early design stages. In order to characterise the viscoelastic isolators, tests have been performed at viscoelastic material level (material characterisation) and at viscoelastic isolator level (isolator characterisation). A qualitative correlation has been established between the master curves (material characterisation) and the transmissibility curves (isolator characterisation) which leads to a possible prediction of expected isolation performances of a viscoelastic material during early design stages.

ANALISA STRATEGI PEMILIHAN MATERIAL PASANGAN DINDING

Wall materials continue to evolve with the demands in achieving the cost, time, quality is the most effective and efficient. The emergence of technology as a light brick wall provides enough material positive impact on society in general and in particular the construction world. This study aims to analyze the material selection strategy that wall pair gain competitive advantage and have the product in accordance with the wishes of consumers and optimal support of existing resources. Light brick is divided into two types, namely lightweight autoclaved Aerated Concrete brick (AAC) and lightweight brick Cellular Lightweight Concrete (CLC), the second type of brick is made of lightweight cement-based materials and sand, which is different is the composition and method of manufacture, light brick AAC dipabrik made through the fabrication process, while the lightweight brick CLC not through the fabrication process. From the analysis, unit price pair of red brick wall USD 101 602 / m², light AAC brick wall USD 123 700 / m², lightweight brick wall CLC Rp 106.700 / m². The results of the three brick lightweight AAC and CLC types are more expensive than the red brick, this is light brick unit price is more expensive than red brick. But in terms of execution time using a lightweight brick 2x faster than using red brick. With SWOT analysis obtained material selection strategy that couples the wall as desired by consumers desired excellence and optimal support of existing resources. So to use the materials in the project planning and it all depends on where the material needs required.

Symbolism among the last hunter–fisher–gatherers in northern Iberia: Personal ornaments from El Mazo and El Toral III Mesolithic shell midden sites

L. obtusata and Trivia sp. shells were systematically used for personal ornamentation by groups who occupied northern Iberia during the Mesolithic. The shells from El Mazo and El Toral III (Asturias, Spain) offer a unique opportunity for investigating raw material procurement, selection strategies, and manufacture processes developed by Asturian Mesolithic societies for beads production. By combining taphonomic, morphometric, and microscopic analyses, our results show that the shells were introduced and transformed in the caves. Mollusk consumption at the sites and bead manufacture indicate that the sites were occupied for both economic and symbolic purposes. The use of similar shell beads by contemporaneous societies located in different environments (coastal and interior) and relying on drastically different subsistence strategies mirrors the complex circulation network developed by Mesolithic foraging societies.

Materials selection for hot stamped automotive body parts: An application of the Ashby approach based on the strain hardening exponent and stacking fault energy of materials

Complex stamping operations are becoming widespread in the automotive industry to produce vehicle body parts with adequate mechanical strength and reduced wall thickness. The need for weight reduction drives the development of new metallic materials capable of achieving a good balance between formability and mechanical properties. Advanced high strength steels play a major role in this scenario. The aim of this work was to develop a materials selection strategy for hot stamped automotive body parts using the Ashby approach. The selection process was based on the formability of metallic alloys derived from two fundamentals materials properties, the strain hardening exponent and the stacking fault energy.

Magnetically multiplexed heating of single domain nanoparticles

Selective hysteretic heating of multiple collocated types of single domain magnetic nanoparticles (SDMNPs) by alternating magnetic fields (AMFs) may offer a useful tool for biomedical applications. The possibility of “magnetothermal multiplexing” has not yet been realized, in part due to prevalent use of linear response theory to model SDMNP heating in AMFs. Dynamic hysteresis modeling suggests that specific driving conditions play an underappreciated role in determining optimal material selection strategies for high heat dissipation. Motivated by this observation, magnetothermal multiplexing is theoretically predicted and empirically demonstrated by selecting SDMNPs with properties that suggest optimal hysteretic heat dissipation at dissimilar AMF driving conditions. This form of multiplexing could effectively offer multiple channels for minimally invasive biological signaling applications.

Lake levels, mobility and lithic raw material selection and reduction strategies: A Great Lakes case study

It has recently been proposed that lowered lake levels after 4250 BP broadened opportunities for mobility and interaction patterns among hunter-gatherer populations in the Saginaw drainage and in Michigan more broadly (; ). Here, data are presented on chipped stone reduction strategies as reflected in two site assemblages in Bay City, Michigan (20BY28, 20BY387) that bridge this key point in time. The earliest Late Archaic components of these sites, occupied during the higher than modern post Nipissing recession ca. 3200 BP, are typified by on-site reduction of local cherts, often utilising a bipolar reduction strategy. Subsequent uses of the area largely shifted to lower elevations. The more recent site components contain both more diverse projectile styles, many of which can be linked with Ontario types, and higher occurrences of non-local raw materials, specifically Onondaga chert apparently arriving at the site as preforms. The last use of these sites occurred during the Late Woodland, also during lower water levels approaching modern, and reflecting the highest use of Onondaga chert. We suggest that these changes resulted from shifting mobility and exchange patterns, facilitated in part by lowered post Nipissing water levels.

Materials Selection Strategy and Surface Treatment of Polymer Composites for Wind Turbine Blades Fabrication

In the present work the optimal materials selection for wind turbine blades using the Cambridge Engineering Selector (CES) program was carried out. Materials indices were derived, based on the mechanical, physical properties and environmental circumstances. Glass and carbon fibre reinforced plastics (epoxy matrix) showed high materials indices based on combined analysis of power and efficiency, fracture toughness, fatigue and thermal stability. Epoxy-glass fibre (EGF) and epoxy-carbon fibre (ECF) composites were manufactured and investigated. Surface of glass and carbon fibre was chemically modified using gamma-aminopropyltriethoxysilane (Silane A1100) coupling agent. The fibre content was varied between 12 to 70% w/w. It is found that the addition of (Silane A1100) as a compatibilizer caused further amelioration of the fibre/matrix bonding resulting in improved mechanical behaviour, which was also, assessed using scanning electron microscopy. Mechanical properties of treated and untreated epoxy composites were illustrated using CES program. Tensile strength of EGF composites was varied based on fibres surface treatment and loadings. Tensile strength of silane treated EGF (70% wt/wt) increased to 1.46 GPa comparing with 1.38 GPa of untreated EGF. The potential and applications of this class of composite materials promise a significant opportunity for improving structural properties of wind turbine blades.

Corrosion in biomass combustion: A materials selection analysis and its interaction with corrosion mechanisms and mitigation strategies

Corrosion induced by chlorine during biomass combustion is a major drawback to the consolidation of this technology. The current literature brings valuable information on these issues. However, a complete assessment of the corrosion mechanisms, mitigation strategies and materials selection for biomass combustion is not encountered. The aim of this work is to develop a materials selection strategy for superheater tubes used in biomass combustion, assessing its interaction with both the corrosion mechanisms and mitigation methods. The Ashby’s approach was used with this purpose.

Optimal multi-material selection for lightweight design of automotive body assembly incorporating recyclability

Multi-material design is known as a material selection strategy used to achieve higher product performance, weight savings and cost reduction. In lightweight designs, weight reduction by using multi-materials will reduce CO2 emission and increase fuel economy, which will significantly reduce environmental impact. Owing to the importance of reducing CO2 emission, automotive designs need to fulfil legislation requirements by attaining higher recyclability value. In this regard, an automotive should be highly recycled at the end of its life in order to extend the use of materials.In response to this problem, this paper presents a novel multi-material selection method for lightweight design, which incorporates recyclability for an automotive body assembly. The method is implemented in a real case study during the conceptual design phase in order to demonstrate its applicability in product design. The proposed method will assist designers to select the optimal combination of multi-materials for lightweight designs, taking into account its recyclability.

Development of plastic front side panels for green cars

Lightweight design with thermoplastics is a robust approach in order to reduce the CO2 emission and fuel consumption. This paper reviews the role of plastics in the green concept of automobile and develops the design process for replacing steel front side panels, so called steel car fender, with plastic ones. Conceptual design, material selection, and design strategy in terms of strength, moldability, and assembility were proposed. Injection molding optimization was carried out in order to ensure the quality of the plastic fender under a certain manufacturing conditions such as the applied molding machine and auxiliary equipment. Prototype manufacturing was also implemented to verify the manufacturability and the feasibility of the development process of a plastic car fender. The weight of the plastic car fender is 1.15kg, reducing 41% compared to the steel fender. Although the production cost of the plastic fender is just slightly cheaper than that of steel one due to the high cost of the special plastic, the benefits such as lightweight, recyclability, manufacturability and design flexibility are the potential and practical application of the thermoplastic to the green automotive industry for making exterior parts.

Octahedral Rotation‐Induced Ferroelectricity in Cation Ordered Perovskites

Electronic structure calculations based on density functional theory have uncovered a novel mechanism for inducing ferroelectric polarizations in cation ordered perovskites. We outline a materials selection strategy for designing this behavior. The guidelines are based on the octahedral rotations found in the two constituent oxides and the way the perovskite building blocks are interwoven to form the superlattice.

Design and material selection guidelines and strategies for transparent armor systems

As evidenced by the recent experience of the US Armed Forces involved in the missions in Iraq and Afghanistan, armoring military-vehicle windshields and side windows is a very challenging task. Apart from providing the required single-hit and multi-hit ballistic protection to the vehicle occupants, the armor must also possess and retain optical transparency and be compatible with on-board imaging and communications equipment. In addition, standard low cost and light-weight requirements are also critical in the design and engineering of transparent armor systems. At the present time, the design and fabrication of transparent armor systems is done almost exclusively using empirical, trial-and-error and legacy approaches. Consequently, new transparent armor system development lead times are long, the costs are quite high and many shortcomings of the systems become apparent only after they have been fielded. To help better understand and overcome this situation, a brief overview and discussion of the basic transparent armor architectures, functional layers and transparent materials is provided and a set of design and material selection guidelines is proposed.