Material Design of High-Damping and High-Strength Composite.

An abundant trait of biological protein materials are hierarchical nanostructures, ranging through atomistic, molecular to macroscopic scales. By utilizing the recently developed Hierarchical Bell Model, here we show that the use of hierarchical structures leads to an extended physical dimension in the material design space that resolves the conflict between disparate material properties such as strength and robustness, a limitation faced by many synthetic materials. We report materiomics studies in which we combine a large number of alpha-helical elements in all possible hierarchical combinations and measure their performance in the strength-robustness space while keeping the total material use constant. We find that for a large number of constitutive elements, most random structural combinations of elements (> 98%) lead to either high strength or high robustness, reflecting the so-called banana-curve performance in which strength and robustness are mutually exclusive properties. This banana-curve type behavior is common to most engineered materials. In contrast, for few, very specific types of combinations of the elements in hierarchies (< 2%) it is possible to maintain high strength at high robustness levels. This behavior is reminiscent of naturally observed material performance in biological materials, suggesting that the existence of particular hierarchical structures facilitates a fundamental change of the material performance. The results suggest that biological materials may have developed under evolutionary pressure to yield materials with multiple objectives, such as high strength and high robustness, a trait that can be achieved by utilization of hierarchical structures. Our results indicate that both the formation of hierarchies and the assembly of specific hierarchical structures play a crucial role in achieving these mechanical traits. Our findings may enable the development of self-assembled de novo bioinspired nanomaterials based on peptide and protein building blocks.

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Fatigue life performance of multi-material connections hybrid joined by self-piercing rivets and adhesive

Materials Testing ◽

10.1515/mt-2020-621003 ◽

2020 ◽

Vol 62 (10) ◽

pp. 973-978

Author(s):

Jan Presse ◽

Thorsten Michler ◽

Boris Künkler

Keyword(s):

Fatigue Life ◽

Lightweight Design ◽

Sheet Thickness ◽

High Strength ◽

Material Design ◽

Design Solution ◽

Cyclic Loads ◽

Dp Steel ◽

Joining Technology ◽

Structural Adhesive

Abstract The multi-material design presented contains EN AW-6016 aluminum and high strength CR330Y590T-DP steel. This dissimilar combination is an example of an affordable lightweight design solution, but it requires an adapted joining technology. Hybrid joining technologies such as selfpiercing riveting (SPR) in combination with a structural adhesive enables an assembly of such dissimilar material combinations. In addition to higher manufacturing costs for mechanical joining the design process still requires a great amount of effort. This study provides a simple approach for assessing hybrid joined multi-material connections. Therefore, tests for several combinations of the most relevant parameters on fatigue life (material properties, sheet thickness, load cases) were performed under quasi-static and cyclic loads. Based on the data acquired, it is shown that the fatigue life of hybrid joined connections can be estimated by superposing the contributing fatigue life of purely SPR and purely adhesive joints.

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Effect of Carbon Pricing on Optimal Mix Design of Sustainable High-Strength Concrete

Sustainability ◽

10.3390/su11205827 ◽

2019 ◽

Vol 11 (20) ◽

pp. 5827 ◽

Cited By ~ 2

Author(s):

Xiao-Yong Wang

Keyword(s):

Co2 Emissions ◽

High Strength Concrete ◽

Cement Content ◽

Gene Expression Programming ◽

High Strength ◽

Material Design ◽

Mix Design ◽

Carbon Pricing ◽

Strength Concrete ◽

Material Cost

Material cost and CO2 emissions are among the vital issues related to the sustainability of high-strength concrete. This research proposes a calculation procedure for the mix design of silica fume-blended high-strength concrete with an optimal total cost considering various carbon pricings. First, the material cost and CO2 emission cost are determined using concrete mixture and unit prices. Gene expression programming (GEP) is used to evaluate concrete mechanical and workability properties. Second, a genetic algorithm (GA) is used to search the optimal mixture, considering various constraints, such as design compressive strength constraint, design workability constraint, range constraints, ratio constraints, and concrete volume constraint. The optimization objective of the GA is the sum of the material cost and the cost of CO2 emissions. Third, illustrative examples are shown for designing various kinds of concrete. Five strength levels (from 95 to 115 MPa with steps of 5 MPa) and four carbon pricings (normal carbon pricing, zero carbon pricing, five-fold carbon pricings, and ten-fold carbon pricings) are considered. A total of 20 optimal mixtures are calculated. The optimal mixtures were found the same for the cases of normal CO2 pricing and zero CO2 pricing. Optimal mixtures with higher strengths are more sensitive to variation in carbon pricing. For five-fold CO2 pricing, the cement content of mixtures with higher strengths (105, 110, and 115 MPa) are lower than those of normal CO2 pricing. As the CO2 pricing increases from five-fold to ten-fold, for mixtures with a strength of 110 MPa, the cement content becomes lower. Summarily, the proposed method can be applied to the material design of sustainable high-strength concrete with low material cost and CO2 emissions.

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Mechanical Requirements of Tailored Joining Technologies for Spring Elements in Multi-Material-Design

Materials Science Forum ◽

10.4028/www.scientific.net/msf.825-826.385 ◽

2015 ◽

Vol 825-826 ◽

pp. 385-392

Author(s):

Arne Busch ◽

Michael Knorre ◽

Robert Brandt

Keyword(s):

High Strength ◽

Material Design ◽

Relative Strength ◽

Spring Steel ◽

Leaf Spring ◽

Basic Study ◽

Glass Fiber Reinforced Plastic ◽

Specific Strength ◽

Glass Fiber Reinforced ◽

Reinforced Plastic

The conflict of targets between mass reduction, strength and costs of a multi-material-design module is addressed by the example of a multi-material hybrid leaf spring. A rather simple model is defined such that one portion of the spring is made by glass fiber reinforced plastic (GFRP) and the other portion by a high strength spring steel.In a rather basic approach the leaf spring is exposed to uniaxial bending. The mass of this module is discussed as a function of the strength of the joint. Subsequently, the leaf spring is exposed to a multi-axial bending, e.g. as an effect of side loads. Hence, the relative strength of the anisotropic portion (GFRP) of the leaf spring is diminished whereas the strength of the isotropic portion (high strength spring steel) is only slightly affected. The mass of the module is discussed in the same way. It is shown up by this analysis that the conflict of targets can be solved in different ways by considering the specific strength of the joint.It is the target of this basic study to derive the mechanical requirement of strength of this tailored joint which has to be met by its design in order to solve the addressed conflict of targets in a preferable optimal way.

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Mechanics of Strong and Tough Cellulose Nanopaper

Applied Mechanics Reviews ◽

10.1115/1.4044018 ◽

2019 ◽

Vol 71 (4) ◽

Cited By ~ 21

Author(s):

Qinghua Meng ◽

Tie Jun Wang

Keyword(s):

Mechanical Properties ◽

Cellulose Nanofibrils ◽

High Strength ◽

Material Design ◽

Design Strategy ◽

Mechanical Modeling ◽

Structure Property ◽

Porous Network ◽

Cellulose Nanopaper ◽

Strength And Toughness

Cellulose nanopaper, which consists of a porous network of cellulose nanofibrils (CNFs), exhibits excellent mechanical properties with high strength and toughness. The physical mechanisms, including a realizable reduction of defect size in the nanopaper and facile formation/reformation of hydrogen bonds among CNFs, suggest a bottom-up material design strategy to address the conflict between strength and toughness. A thorough exploration of the rich potential of such a design strategy requires a fundamental understanding of its mechanical behavior. In this review, we supply a comprehensive perspective on advances in cellulose nanopaper mechanics over the most recent two decades from the three aspects of mechanical properties, structure–property relationship and microstructure-based mechanical modeling. We discuss the effects of size, orientation, polymerization degree, and isolate origins of CNFs; density or porosity and humidity of nanopaper; and hemicellulose and lignin on the mechanical properties of cellulose nanopaper. We also discuss the similarities and differences in the microstructure, mechanical properties, and toughening mechanisms between cellulose nanopaper and cellulose nanocrystal (CNC) nanopaper, chitin nanopaper, carbon nanotube (CNT) nanopaper, and graphene nanopaper. Finally, we present the ideas, status quo, and future trends in mechanical modeling of cellulose nanopaper, including atomistic- and microscale-level numerical modeling, and theoretical modeling. This review serves as a modest spur intended to induce scientists to present their valuable contributions and especially to design more advanced cellulose nanopapers and promote the development of their mechanics.

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420 Material Design and Application of SPS for the Improvement of Wear Resistance of High-Strength Steel

The Proceedings of Conference of Kyushu Branch ◽

10.1299/jsmekyushu.2014.67._420-1_ ◽

2014 ◽

Vol 2014.67 (0) ◽

pp. _420-1_-_420-2_

Author(s):

Ayako NAGASE ◽

Takuya NAKAMURA ◽

Kosei IDICHI ◽

Yuzo NAKAMURA ◽

Ryuichi IWAMOTO

Keyword(s):

Wear Resistance ◽

High Strength Steel ◽

High Strength ◽

Material Design ◽

Design And Application

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Design and Construction of the Cofferdam Pile with GFRP Reinforced Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.671-674.437 ◽

2013 ◽

Vol 671-674 ◽

pp. 437-440 ◽

Cited By ~ 1

Author(s):

Ming Lei Ma ◽

Gui Ling Wang ◽

Dong Mei Miao ◽

Bao Yu Lian

Keyword(s):

Weight Ratio ◽

Volume Ratio ◽

High Strength ◽

Material Design ◽

Fiber Volume ◽

Nanjing City ◽

Frp Reinforcement ◽

Railway Engineering ◽

Design And Construction

FRP (Fiber reinforced polymer) is a two-way designed material from both macro and micro design. Former design was carried out according to the structural design, and the micro design is the material design on fiber volume ratio and the resin types. FRP is eminent in civil engineering because of its high strength to weight ratio, durability prolongation, high stiffness to weight ratio and its fatigue resistance behaviors. Right now, lots of applications were found in offshore engineering, hydraulic engineering and railway engineering. This article focused on both design and construction of the FRP reinforcement with concrete, and a case study was provided from the Nanjing city by CCEED (China Construction Eighth Engineering Division).

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Material Design Methodology for Optimized Wear-Resistant Thermoplastic–Matrix Composites Based on Polyetheretherketone and Polyphenylene Sulfide

Materials ◽

10.3390/ma13030524 ◽

2020 ◽

Vol 13 (3) ◽

pp. 524 ◽

Cited By ~ 1

Author(s):

Sergey V. Panin ◽

Boris A. Lyukshin ◽

Svetlana A. Bochkareva ◽

Lyudmila A. Kornienko ◽

Duc Ahn Nguyen ◽

...

Keyword(s):

Design Methodology ◽

High Strength ◽

Material Design ◽

Polyphenylene Sulfide ◽

Matrix Composites ◽

Wear Resistant ◽

Mechanical And Tribological Properties ◽

Thermoplastic Matrix ◽

The Matrix ◽

Carbon Microfibers

The main goal of this paper is to design and justify optimized compositions of thermoplastic–matrix wear-resistant composites based on polyetheretherketone (PEEK) and polyphenylene sulfide (PPS). Their mechanical and tribological properties have been specified in the form of bilateral and unilateral limits. For this purpose, a material design methodology has been developed. It has enabled to determine the optimal degrees of filling of the PEEK- and PPS-based composites with carbon microfibers and polytetrafluoroethylene particles. According to the results of tribological tests, the PEEK-based composites have been less damaged on the metal counterpart than the PPS-based samples having the same degree of filling. Most likely, this was due to more uniform permolecular structure and greater elasticity of the matrix. The described methodology is versatile and can be used to design various composites. Its implementation does not impose any limits on the specified properties of the material matrix or the reinforcing inclusions. The initial data on the operational characteristics can be obtained experimentally or numerically. The methodology enables to design the high-strength wear-resistant composites which are able to efficiently operate both in metal–polymer and ceramic–polymer friction units.

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Nanoscale precipitates as sustainable dislocation sources for enhanced ductility and high strength

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1914615117 ◽

2020 ◽

Vol 117 (10) ◽

pp. 5204-5209 ◽

Cited By ~ 4

Author(s):

Shenyou Peng ◽

Yujie Wei ◽

Huajian Gao

Keyword(s):

Lattice Mismatch ◽

High Stress ◽

High Strength ◽

Material Design ◽

Dislocation Nucleation ◽

Precipitate Size ◽

Unique Type ◽

Dislocation Glide ◽

High Stress Concentration ◽

Dislocation Sources

Traditionally, precipitates in a material are thought to serve as obstacles to dislocation glide and cause hardening of the material. This conventional wisdom, however, fails to explain recent discoveries of ultrahigh-strength and large-ductility materials with a high density of nanoscale precipitates, as obstacles to dislocation glide often lead to high stress concentration and even microcracks, a cause of progressive strain localization and the origin of the strength–ductility conflict. Here we reveal that nanoprecipitates provide a unique type of sustainable dislocation sources at sufficiently high stress, and that a dense dispersion of nanoprecipitates simultaneously serve as dislocation sources and obstacles, leading to a sustainable and self-hardening deformation mechanism for enhanced ductility and high strength. The condition to achieve sustainable dislocation nucleation from a nanoprecipitate is governed by the lattice mismatch between the precipitate and matrix, with stress comparable to the recently reported high strength in metals with large amount of nanoscale precipitates. It is also shown that the combination of Orowan’s precipitate hardening model and our critical condition for dislocation nucleation at a nanoprecipitate immediately provides a criterion to select precipitate size and spacing in material design. The findings reported here thus may help establish a foundation for strength–ductility optimization through densely dispersed nanoprecipitates in multiple-element alloy systems.

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Material Design for High Strength NTC Thermistor Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.350.229 ◽

2007 ◽

Vol 350 ◽

pp. 229-232 ◽

Cited By ~ 1

Author(s):

Tadamasa Miura ◽

Akinori Nakayama ◽

Hideaki Niimi ◽

Hiroshi Tamura

Keyword(s):

Compressive Stress ◽

Negative Temperature Coefficient ◽

Stress Measurement ◽

Spinel Phase ◽

High Strength ◽

Material Design ◽

Negative Temperature ◽

Ntc Thermistor ◽

Typical Composition ◽

Salt Phase

Various factors were investigated to decide the mechanical properties of (Mn1–xNix)3O4 ceramics, that are typical composition systems of NTC (negative temperature coefficient) thermistors. The strength of NTC thermistor ceramics can be improved by designing the material so that the compressive stress may remain at the surface of the ceramics. At high temperature, the thermal expansion coefficient of a rock salt phase segregated internally ceramic increases over that of the spinel phase, further, on the surface of the ceramics, this compressive stress remains below room temperature. Moreover, it was confirmed that the stress analysis result by the FEM corresponded well with the stress measurement result on the surface of the ceramics measured by μ -XRD.

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