Investigating the molecular mechanisms and mechanical properties of epithelial keratin and trichocyte keratin using multiscale modelling

Establishing a deeper understanding of the molecular mechanisms and mechanical properties of materials can help improve engineering processes and also contribute to establishing a better understanding of diseases and how they can be treated. A better understanding of the exact structures and mechanisms of a material and how they affect a material's properties, can lead to the development of new, novel materials that can respond to societal needs. Assistant Professor Chia-Ching Chou, Institute of Applied Mechanics, National Taiwan University, Taiwan, is working to better understand the intricacies of materials by taking inspiration from nature, with a particular focus on two types of keratin. Chou and her team are using molecular modelling to investigate the molecular mechanisms and mechanical properties of epithelial keratin and trichocyte keratin. Trichocyte keratin, otherwise known as hair keratin, is durable and has had a number of applications in engineering for many years, while epithelial keratin, which is also known as skin keratin, cannot sustain the same load as hair keratin, but has a greater ability to be stretched, and is therefore of interest to the team. Chou and the team are investigating how the molecular compositions of trichocyte keratin and epithelial keratin affect the mechanical properties. To do this, the researchers are performing molecular dynamics simulation using atomistic and multiscale computational modelling, which allows them to explore the composition, structure and behaviour of keratin at the molecular level. Ultimately, the researchers want to determine how sequence and chemical bonding affect the microscopic, mesoscopic and macroscopic level properties of materials.

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The Marker Conservation Law in Multiphase Systems

High Temperature Materials and Processes ◽

10.1515/htmp-2014-0189 ◽

2016 ◽

Vol 35 (2) ◽

pp. 209-214 ◽

Cited By ~ 1

Author(s):

Bartek Wierzba ◽

Stanisław Wędrychowicz ◽

Wojciech Skibiński

Keyword(s):

Experimental Data ◽

Mechanical Properties ◽

Mechanical Property ◽

Kirkendall Effect ◽

Ti Alloy ◽

Multicomponent Systems ◽

Multiphase Systems ◽

Fundamental Understanding ◽

Properties Of Materials ◽

Composition Structure

AbstractThe knowledge of the fundamental understanding such as composition–structure–mechanical property relationships caused by Kirkendall effect is in progress and is used to optimize mechanical properties of materials. In this paper the multiphase systems with low non-stoichiometry are discussed. It is shown that in such systems the drift velocity can be approximated as constant in each phase and determined by Wagner’s integral diffusivity. In this paper the binary in Ni–Ti alloy is discussed; however, the method can be applied to multicomponent systems. The results of the calculations are compared with experimental data.

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Mechanics of Microfilaments Networks: A Cross-Scales Study

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.553.310 ◽

2014 ◽

Vol 553 ◽

pp. 310-315

Author(s):

Tong Li ◽

Yuan Tong Gu ◽

Bao Cheng Zhang

Keyword(s):

Mechanical Properties ◽

Molecular Mechanisms ◽

Mechanical Stability ◽

Dynamics Simulation ◽

Coarse Grained ◽

Cellular Structures ◽

Modelling Framework ◽

Simulation Strategy ◽

Mechanical Models ◽

Mechanical Behaviours

The mechanical properties of microfilament networks are systematically summarized at different special scales in this paper. We have presented the mechanical models of single microfilaments and microfilament networks at microscale. By adopting a coarse-grained simulation strategy, the mechanical stability of microfilaments related cellular structures are analysed. Structural analysis is conducted to microfilament networks to understand the stress relaxation under compression. The nanoscale molecular mechanisms of the microfilaments deformation is also summarized from the viewpoint of molecular dynamics simulation. This paper provides the fundaments of multiscale modelling framework for the mechanical behaviours simulation of hierarchical microfilament networks.

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Analysis of Operation of a Driving Band Mounting in a Projectile’s Shell

Problems of Mechatronics Armament Aviation Safety Engineering ◽

10.5604/01.3001.0012.1100 ◽

2018 ◽

Vol 9 (2) ◽

pp. 45-58

Author(s):

Mieczysław KACZOROWSKI ◽

Zdzisław LINDEMANN ◽

Marek RADOMSKI

Keyword(s):

Mechanical Properties ◽

Finite Element Method ◽

Residual Stresses ◽

Computational Modelling ◽

Technological Operation ◽

The Finite Element Method ◽

Factors Influencing ◽

Properties Of Materials ◽

Significant Factors

The paper presents computational modelling using the Finite Element Method (FEM) for technological operation of a driving band mounted in a groove of a projectile shell. Exemplary results of analysis for shrapnel cal. 35 mm are given. The analysis showed significant factors influencing the mounting process and a field of residual stresses in a projectile shell. It allowed for determination of mechanical properties of materials of a driving band and a projectile shell as well as of characteristic dimensions of half-finished product of a driving band and a groove in a projectile shell. The obtained investigation results show substantial advantages of such analyses for a design process of new types of gunnery ammunition. Thus, it is possible to optimise the construction and technology, i.e., to minimise the reduced stresses in a field of residual stresses in a projectile shell what limits the possibility of a driving band break (rupture) or cracking a projectile shell inside a barrel during the shot.

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Controlling microstructure

Impact ◽

10.21820/23987073.2020.1.46 ◽

2020 ◽

Vol 2020 (1) ◽

pp. 46-47

Author(s):

Takahiro Kunimine

Keyword(s):

Mechanical Properties ◽

Materials Science ◽

High Hardness ◽

High Strength ◽

Assistant Professor ◽

Functionally Graded ◽

Japan Society ◽

Graded Materials ◽

Coarse Grains ◽

Properties Of Materials

Most conventional materials have a microstructure comprised of minute, usually coarse, grains. One branch of materials science targets this microstructure as a means to manipulating the mechanical properties of materials to offer greater strength and hardness. Dr Takahiro Kunimine, an Assistant Professor from the Faculty of Mechanical Engineering at Kanazawa University, has recently completed a project focused on using severe plastic deformation (SPD) to develop nanostructured materials with high strength. His current project has been focusing on processing functionally graded materials with high hardness and toughness by additive manufacturing. These works, supported by Japan Society for the Promotion of Science (JSPS) KAKENHI grant, led to the development of much stronger materials.

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Effect of Machining-Induced Subsurface Defects on Dislocation Evolution and Mechanical Properties of Materials via Nano-indentation

Nanoscale Research Letters ◽

10.1186/s11671-019-3212-7 ◽

2019 ◽

Vol 14 (1) ◽

Author(s):

Quanlong Wang ◽

Meiping Wu ◽

Chaofeng Zhang ◽

Yanming Lv ◽

Xiaogang Ji

Keyword(s):

Mechanical Properties ◽

Interaction Mechanism ◽

Dynamics Simulation ◽

Indentation Hardness ◽

Secondary Processing ◽

Nano Indentation ◽

Mechanical Properties Of Materials ◽

Properties Of Materials ◽

And Performance ◽

Subsurface Defects

AbstractSubsurface defects have a significant impact on the precision and performance of nano-structures. In this paper, molecular dynamics simulation of nano-indentation is performed to investigate the effect of machining-induced subsurface defects on dislocation evolution and mechanical properties of materials, in which the specimen model with subsurface defects is constructed by nano-cutting conforming to reality. The formation mechanism of subsurface defects and the interaction mechanism between machine-induced defects and dislocation evolution are discussed. The hardness and Young’s elastic modulus of single crystal copper specimens are calculated. The simulation results indicate that there exist stable defect structure residues in the subsurface of workpiece, such as atomic clusters, stacking fault tetrahedral, and stair-rod dislocations. Secondary processing of nano-indentation can restore internal defects of the workpiece, but the subsurface damage in the secondary processing area is aggravated. The nano-indentation hardness of specimens increases with the introduction of subsurface defects, which results in the formation of work-hardening effect. The existence of subsurface defects can weaken the ability of material to resist elastic deformation, in which the mutual evolution between dislocations and subsurface defects plays an important role.

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