Open Access. Powered by Scholars. Published by Universities.®

Mechanics of Materials Commons

Open Access. Powered by Scholars. Published by Universities.®

1,662 Full-Text Articles 2,785 Authors 333,896 Downloads 64 Institutions

All Articles in Mechanics of Materials

Faceted Search

1,662 full-text articles. Page 7 of 53.

Design Rules For Additive Manufacturing – Understanding The Fundamental Thermal Phenomena To Reduce Scrap, M. Reza Yavari, Kevin D. Cole, Prahalada K. Rao 2019 University of Nebraska-Lincoln

Design Rules For Additive Manufacturing – Understanding The Fundamental Thermal Phenomena To Reduce Scrap, M. Reza Yavari, Kevin D. Cole, Prahalada K. Rao

Mechanical & Materials Engineering Faculty Publications

The goal of this work is to predict the effect of part geometry and process parameters on the direction and magnitude of heat flow heat flux in parts made using metal additive manufacturing (AM) processes. As a step towards this goal, the objective of this paper is to develop and apply the mathematical concept of heat diffusion over graphs to approximate the heat flux in metal AM parts as a function of their geometry. This objective is consequential to overcome the poor process consistency and part quality in AM. Currently, part build failure rates in metal AM often exceed 20 ...


Spatiotemporal Characterizations Of Spontaneously Beating Cardiomyocytes With Adaptive Reference Digital Image Correlation, Akankshya Shradhanjali, Brandon D. Riehl, Bin Duan, Ruiguo Yang, Jung Yul Lim 2019 University of Nebraska-Lincoln

Spatiotemporal Characterizations Of Spontaneously Beating Cardiomyocytes With Adaptive Reference Digital Image Correlation, Akankshya Shradhanjali, Brandon D. Riehl, Bin Duan, Ruiguo Yang, Jung Yul Lim

Mechanical & Materials Engineering Faculty Publications

We developed an Adaptive Reference-Digital Image Correlation (AR-DIC) method that enables unbiased and accurate mechanics measurements of moving biological tissue samples. We applied the AR-DIC analysis to a spontaneously beating cardiomyocyte (CM) tissue, and could provide correct quantifications of tissue displacement and strain for the beating CMs utilizing physiologically-relevant, sarcomere displacement length-based contraction criteria. The data were further synthesized into novel spatiotemporal parameters of CM contraction to account for the CM beating homogeneity, synchronicity, and propagation as holistic measures of functional myocardial tissue development. Our AR-DIC analyses may thus provide advanced non-invasive characterization tools for assessing the development of spontaneously ...


Optimization Of Protein-Protein Interaction Measurements For Drug Discovery Using Afm Force Spectroscopy, Yongliang Yang, Bixi Zeng, Zhiyong Sun, Amir Monemianesfahani, Jing Hou, Nian-Dong Jiao, Lianqing Liu, Liangliang Chen, Marc D. Basson, Lixin Dong, Ruiguo Yang, Ning Xi 2019 Michigan State University

Optimization Of Protein-Protein Interaction Measurements For Drug Discovery Using Afm Force Spectroscopy, Yongliang Yang, Bixi Zeng, Zhiyong Sun, Amir Monemianesfahani, Jing Hou, Nian-Dong Jiao, Lianqing Liu, Liangliang Chen, Marc D. Basson, Lixin Dong, Ruiguo Yang, Ning Xi

Mechanical & Materials Engineering Faculty Publications

Increasingly targeted in drug discovery, protein-protein interactions challenge current high throughput screening technologies in the pharmaceutical industry. Developing an effective and efficient method for screening small molecules or compounds is critical to accelerate the discovery of ligands for enzymes, receptors and other pharmaceutical targets. Here, we report developments of methods to increase the signal-to-noise ratio (SNR) for screening protein-protein interactions using atomic force microscopy (AFM) force spectroscopy. We have demonstrated the effectiveness of these developments on detecting the binding process between focal adhesion kinases (FAK) with protein kinase B (Akt1), which is a target for potential cancer drugs. These developments ...


Compliant Surgical Graspers And Methods Of Making And Using, Carl Nelson, Alan Goyzueta 2019 Lincoln, NE

Compliant Surgical Graspers And Methods Of Making And Using, Carl Nelson, Alan Goyzueta

Mechanical & Materials Engineering Faculty Publications

This disclosure describes compliant graspers for use in endoscopic surgeries.


Nonlinear Optical Responses In Type-Ii Weyl Semimetals, Gerui Liu 2019 University of Pennsylvania

Nonlinear Optical Responses In Type-Ii Weyl Semimetals, Gerui Liu

Publicly Accessible Penn Dissertations

Weyl semimetals are gapless topological states of matter with broken inversion and/or time reversal symmetry. In this thesis, we will firstly discuss the observation of a novel photogalvanic effect in type-II Weyl semimetals including $\rm T_d-MoTe_2$, $\rm Mo_{0.9}W_{0.1}Te_2$ and $\rm Mo_{0.3}W_{0.7}Te_2$. A circulating photocurrent is obtained under the illumination of normally incident light with circular polarization and the circulating current direction is opposite with different light helicity. Through temperature induced phase transition of $\rm MoTe_2$, this effect is further confirmed to exclusively occur in the Weyl phase ...


Study Of Behavior Of Plastic Modified Bitumen By Incorporating Carbon Black, Ho-Fai Wong, Hao-Jue Hong, Lai-Ming Leung, Tsz-Chun Fong, Yi-Fei Shen, Tsz-Hin Lo 2019 Technological and Higher Education Institute of Hong Kong (THEi)

Study Of Behavior Of Plastic Modified Bitumen By Incorporating Carbon Black, Ho-Fai Wong, Hao-Jue Hong, Lai-Ming Leung, Tsz-Chun Fong, Yi-Fei Shen, Tsz-Hin Lo

Technological and Higher Education Institute of Hong Kong (THEi) Staff Publications

In recent years, the performance of polymer modified bitumen has been widely studied. This study reports a research carried out to investigate the properties of polymer modified bitumen (PMB) by using polypropylene as modifier, carbon black as additives, to examine the optimum ratio of polypropylene to carbon black. With this objective, sample preparation using wet mixing method combining high shear mix was firstly performed. Subsequently, 18 samples were developed for the study, of which the polypropylene (PP) contents 10%, 12%, 14%, 16%, 18% and 20% with 2%, 3%, 4% of carbon black content. Afterwards, samples were characterized by standard tests ...


Predicting Dynamic Modulus Of Asphalt Mixture Using Data Obtained From Indirect Tension Mode Of Testing, Parnian Ghasemi, Shibin Lin, Derrick K. Rollins, R. Christopher Williams 2019 Iowa State University

Predicting Dynamic Modulus Of Asphalt Mixture Using Data Obtained From Indirect Tension Mode Of Testing, Parnian Ghasemi, Shibin Lin, Derrick K. Rollins, R. Christopher Williams

Chemical and Biological Engineering Publications

Understanding stress-strain behavior of asphalt pavement under repetitive traffic loading is of critical importance to predict pavement performance and service life. For viscoelastic materials, the stress-strain relationship can be represented by the dynamic modulus. The dynamic modulus test in indirect tension mode can be used to measure the modulus of each specific layer of asphalt pavements using representative samples. Dynamic modulus is a function of material properties, loading, and environmental conditions. Developing predictive models for dynamic modulus is efficient and cost effective. This article focuses on developing an accurate Finite Element (FE) model using mixture elastic modulus and asphalt binder ...


Selective Conversion Of Biomass Model Compounds Using Promoted Metal Catalysts, Cong Wang 2019 University of Pennsylvania

Selective Conversion Of Biomass Model Compounds Using Promoted Metal Catalysts, Cong Wang

Publicly Accessible Penn Dissertations

ABSTRACT

SELECTIVE CONVERSION OF BIOMASS MODEL COMPOUNDS USING PROMOTED METAL CATALYSTS

Cong Wang

Raymond J. Gorte

Extensive research and development have gone into modern biomass upgrading in order to mitigate the environmental concerns and other impending challenges associated with conventional fuels and chemicals. The phenolic and furanic compounds produced by primary upgrading processes represent a collection of biomass intermediates that still preserve the valuable chemical structures, but they require further upgrading due to unfavorable oxygen contents and unstable functional groups. This dissertation seeks to demonstrate the viability of utilizing bimetallic and metal-oxide-promoted metal catalysts to further upgrade biomass-derived oxygenates by ...


Deformation Correlations And Machine Learning: Microstructural Inference And Crystal Plasticity Predictions, Michail Tzimas 2019 West Virginia University

Deformation Correlations And Machine Learning: Microstructural Inference And Crystal Plasticity Predictions, Michail Tzimas

Graduate Theses, Dissertations, and Problem Reports

The present thesis makes a connection between spatially resolved strain correlations and material processing history. Such correlations can be used to infer and classify prior deformation history of a sample at various strain levels with the use of Machine Learning approaches. A simple and concrete example of uniaxially compressed crystalline thin films of various sizes, generated by two-dimensional discrete dislocation plasticity simulations is examined. At the nanoscale, thin films exhibit yield-strength size effects with noisy mechanical responses which create an interesting challenge for the application of Machine Learning techniques. Moreover, this thesis demonstrates the prediction of the average mechanical responses ...


Towards Understanding Material Characteristics Through The Additive Manufacturing Arc, Alden Watts 2019 Iowa State University

Towards Understanding Material Characteristics Through The Additive Manufacturing Arc, Alden Watts

Graduate Theses and Dissertations

The directed energy powder feed additive manufacturing (AM) process fabricates components with good quality, accuracy, and efficiency. However, this is a complex process and without careful consideration can lead to discontinuities in the final product such as porosity, cracks, or unfavorable microstructure. These material discontinuities may occur due to the limited understanding of the relationship between AM source materials and the evolution of the composition and microstructure during the deposition process. This makes it vital to study and correlate the composition, morphology, and characteristics of both the source material and of the final printed parts. In this research the properties ...


Processing, Structure And Mechanical Behavior Of Advanced Engineering Steels, Bing Yu 2019 University of Texas at El Paso

Processing, Structure And Mechanical Behavior Of Advanced Engineering Steels, Bing Yu

Open Access Theses & Dissertations

The concept of low lattice misfit and high-density of nanoscale precipitates obtained through solution treatment was adopted to obtain ultrahigh strength maraging steel without compromising elongation. An "ultrahigh strength-high toughness" combination was successfully obtained in 19Ni3Mo1.5Ti maraging steel with ultimate strength of ~1858 MPa and static toughness of ~110 MJ·m-3. Maraging steel had extremely high density (2.3�1024 m-3) of nanoscale precipitates with minimum lattice misfit of less than 1% at the solutionization temperature of 820 oC. Two kinds of nanoscale precipitates, namely, η-Ni3(Ti,Mo) and B2-Ni(Mo,Fe) contributed to ultrahigh strength. The size ...


Microstructure Evolution Of Chalcogenide Materials Via Molecular Dynamics, Sharmin Abdullah 2019 University of Texas at El Paso

Microstructure Evolution Of Chalcogenide Materials Via Molecular Dynamics, Sharmin Abdullah

Open Access Theses & Dissertations

The properties of a material are defined by its granular microstructure which is determined by its grain evolution and the types of grain boundaries present in the structure. For example, the performance of Cadmium Sulfide/Cadmium Telluride (CdS/CdTe) solar cells can be affected by the presence of grain boundaries which makes the study of grain structure evolution a very important part of solar cell performance optimization. Grain boundary mobilities are important properties in material science and engineering as they determine grain structures under given processing and operating conditions.

In this thesis, several computational tools were used to analyze the ...


Design And Development Of Cellulose Based Composites For The Built Environment, Melvin Glenn Veigas 2019 Iowa State University

Design And Development Of Cellulose Based Composites For The Built Environment, Melvin Glenn Veigas

Graduate Theses and Dissertations

Cellulose is a versatile material with numerous contemporary applications in textiles, food, and biomaterials. Contemporary research is focused on modifying the structural and thermal properties of cellulose to create novel composites with cellulose nano-crystals, lignocellulosic pulp, and foamed cellulose to name a few. Significant advances have been made in improving the properties of cellulose. Adding aligned cellulose nano-fibers to concrete to improve its mechanical properties or combining with polymers for better durability can lead to new applications specifically in design and construction. These new forms of cellulose through optimization and combination with other materials provide opportunities for reducing material usage ...


Liquid Metal-Elastomer Soft Composites With Independently Controllable And Highly Tunable Droplet Size And Volume Loading, Ravi Tutika, Steven Kmiec, A. B. M. Tahidul Haque, Steve W. Martin, Michael D. Bartlett 2019 Iowa State University

Liquid Metal-Elastomer Soft Composites With Independently Controllable And Highly Tunable Droplet Size And Volume Loading, Ravi Tutika, Steven Kmiec, A. B. M. Tahidul Haque, Steve W. Martin, Michael D. Bartlett

Materials Science and Engineering Publications

Soft composites are critical for soft and flexible materials in energy harvesting, actuators, and multifunctional devices. One emerging approach to create multifunctional composites is through the incorporation of liquid metal (LM) droplets such as eutectic gallium indium (EGaIn) in highly deformable elastomers. The microstructure of such systems is critical to their performance, however, current materials lack control of particle size at diverse volume loadings. Here, we present a fabrication approach to create liquid metal-elastomer composites with independently controllable and highly tunable droplet size (100 nm ≦ D ≦ 80 μm) and volume loading (0 ≦ φ ≦ 80%). This is achieved through a combination ...


Mechanical Properties And Degradation Of High Capacity Battery Electrodes: Fundamental Understanding And Coping Strategies, Yikai Wang 2019 University of Kentucky

Mechanical Properties And Degradation Of High Capacity Battery Electrodes: Fundamental Understanding And Coping Strategies, Yikai Wang

Theses and Dissertations--Chemical and Materials Engineering

Rechargeable lithium ion and lithium (Li) metal batteries with high energy density and stability are in high demand for the development of electric vehicles and smart grids. Intensive efforts have been devoted to developing high capacity battery electrodes. However, the known high capacity electrode materials experience fast capacity fading and have limited cycle life due to electromechanical degradations, such as fracture of Si-based electrodes and dendrite growth in Li metal electrodes. A fundamental understanding of electromechanical degradation mechanisms of high capacity electrodes will provide insights into strategies for improving their electrochemical performance. Thus, this dissertation focuses on mechanical properties, microstructure ...


Efficient Solar-To-Thermal Energy Conversion And Storage With High-Thermal-Conductivity And Form-Stabilized Phase Change Composite Based On Wood-Derived Scaffolds, Bolin Chen, Meng Han, Bowei Zhang, Gaoyuan Ouyang, Behrouz Shafei, Xinwei Wang, Shan Hu 2019 Iowa State University

Efficient Solar-To-Thermal Energy Conversion And Storage With High-Thermal-Conductivity And Form-Stabilized Phase Change Composite Based On Wood-Derived Scaffolds, Bolin Chen, Meng Han, Bowei Zhang, Gaoyuan Ouyang, Behrouz Shafei, Xinwei Wang, Shan Hu

Mechanical Engineering Publications

Solar-to-thermal energy conversion is one of the most efficient ways to harvest solar energy. In this study, a novel phase change composite with porous carbon monolith derived from natural wood is fabricated to harvest solar irradiation and store it as thermal energy. Organic phase change material n-octadecane is physically adsorbed inside the porous structure of the carbonized wood, and a thin graphite coating encapsulates the exterior of the wood structure to further prevent n-octadecane leakage. The carbonized wood scaffold and the graphite coating not only stabilize the form of the n-octadecane during phase change, but also enhance its thermal conductivity ...


In Situ Quantitative Study Of Plastic Strain-Induced Phase Transformations Under High Pressure: Example For Ultra-Pure Zr, K. K. Pandey, Valery I. Levitas 2019 Iowa State University

In Situ Quantitative Study Of Plastic Strain-Induced Phase Transformations Under High Pressure: Example For Ultra-Pure Zr, K. K. Pandey, Valery I. Levitas

Aerospace Engineering Publications

First in situ quantitative synchrotron X-ray diffraction (XRD) study of plastic strain-induced phase transformation (PT) has been performed on α−ω PT in ultra-pure Zr as an example under different compression-shear pathways in rotational diamond anvil cell (RDAC). Radial distributions of pressure in each phase and in the mixture, and concentration of ω-Zr, all averaged over the sample thickness, as well as thickness profile were measured. The yield strength of both phases is estimated to be practically the same, in strong contrast to known estimates. Minimum pressure for the strain-induced α−ω PT, 1.2 GPa, is smaller by a ...


Fe Modeling Methodology For Load Analysis And Preliminary Sizing Of Aircraft Wing Structure, Jun Hwan Jang, Sang Ho Ahn 2019 Defense Acquisition Program Administration

Fe Modeling Methodology For Load Analysis And Preliminary Sizing Of Aircraft Wing Structure, Jun Hwan Jang, Sang Ho Ahn

International Journal of Aviation, Aeronautics, and Aerospace

It is a critical part at the basic design phase of aircraft structural design to build a finite element model and it will have a direct impact on time and cost for airframe structure development. In addition, the objective of finite element model will be varied depending on each design review phase and the modelling methodology varied accordingly. In order to build an effective and economic finite element model, it is required to develop adequate level of modelling methodology based on each design phase and its objectives. Therefore, in this paper, the finite element modeling methodology was presented for internal ...


Investigation Of The Evolution Of Hydrophobicity And Wettability Of Paper In Multi-Color Printing Process, C Aydemir, A Karademir, S Imamoglu, Bilge N. Altay, Paul D. Fleming, D Tutak 2018 Marmara University

Investigation Of The Evolution Of Hydrophobicity And Wettability Of Paper In Multi-Color Printing Process, C Aydemir, A Karademir, S Imamoglu, Bilge N. Altay, Paul D. Fleming, D Tutak

Bilge Nazli Altay

One of the keys to improving print quality is to experimentally characterize the paper surface, structure and printability to obtain quality control mechanisms. In multi-color prints, determining the differences in the acceptance of the next color ink by the surface of the paper or the ink film that was previously printed is important for print quality. The criteria, such as ink setting, adhesion, color, gloss and density, in the printing process, depend on the wettability and absorbency of the paper. The surface structure of the paper is the most important factor in determining the hydrophobic properties. In this study, wetting ...


Tunable Electronic And Optical Properties Of Low-Dimensional Materials, Shiyuan Gao 2018 Washington University in St. Louis

Tunable Electronic And Optical Properties Of Low-Dimensional Materials, Shiyuan Gao

Arts & Sciences Electronic Theses and Dissertations

Two-dimensional (2D) materials with single or a few atomic layers, such as graphene, hexagonal boron nitride (h-BN) and transition metal dichalcogenides (TMDCs), and the heterostructures or one-dimensional (1D) nanostructures they form, have attracted much attention recently as unique platforms for studying many condensed-matter phenomena and holds great potentials for nanoelectronics and optoelectronic applications. Apart from their unique intrinsic properties which has been intensively studied for over a decade by now, they also allow external control of many degrees of freedom, such as electrical gating, doping and layer stacking. In this thesis, I present a theoretical study of the electronic and ...


Digital Commons powered by bepress