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Full-Text Articles in Engineering

Laser Assisted Embedding Of Nanoparticles Into Metallic Materials, Dong Lin, Sergey Suslov, Chang Ye, Yiliang Liao, C. Liu, Gary Cheng Apr 2015

Laser Assisted Embedding Of Nanoparticles Into Metallic Materials, Dong Lin, Sergey Suslov, Chang Ye, Yiliang Liao, C. Liu, Gary Cheng

Dr. Chang Ye

This paper reports a methodology of half-embedding nanoparticles into metallic materials. Transparent and opaque nanoparticles are chosen to demonstrate the process of laser assisted nanoparticle embedding. Dip coating method is used to coat transparent or opaque nanoparticle on the surface of metallic material. Nanoparticles are embedded into substrate by laser irradiation. In this study, the mechanism and process of nanoparticle embedding are investigated. It is found both transparent and opaque nanoparticles embedding are with high densities and good uniformities.


Mechanism Of Fatigue Performance Enhancement In A Superhard Nanoparticles Integrated Nanocomposites By A Hybrid Manufacturing Technique, Dong Lin, Chang Ye, Yiliang Liao, C. Liu, Gary Cheng Apr 2015

Mechanism Of Fatigue Performance Enhancement In A Superhard Nanoparticles Integrated Nanocomposites By A Hybrid Manufacturing Technique, Dong Lin, Chang Ye, Yiliang Liao, C. Liu, Gary Cheng

Dr. Chang Ye

A hybrid manufacturing process, which contains Laser Sintering (LS) and Laser shock peening (LSP), is introduced to generate iron-TiN nanoparticle nanocomposites. It is a two-step process including LS followed with LSP. Before LS, TiN nanoparticles mixed with iron powders are coated on samples surface. After LS, TiN nanoparticles are embedded into iron matrix to strengthen materials. Then LSP is performed to introduce work hardening and compressive residual stress. The existed nanoparticles increase the dislocation density and also help to pin the dislocation movement. Better residual stress stability under thermal annealing can be obtained by better dislocation movement stabilization, which is …


Numerical Simulation On Nanoparticles Integrated Laser Shock Peening Of Aluminum Alloy, Chang Ye, Gary Cheng Apr 2015

Numerical Simulation On Nanoparticles Integrated Laser Shock Peening Of Aluminum Alloy, Chang Ye, Gary Cheng

Dr. Chang Ye

In this paper, numerical simulation of nanoparticle integrated laser shock peening of aluminum alloys was carried out. A “tied constraint” was used to connect the matrix and nanoparticle assembly in ABAQUS package. Different particle size and particle volumes fraction (PVF) were studied. It was found that there is significant stress concentration around the nanoparticles. The existence of nanoparticle will influence the stress wave propagation and thus the final stress and strain state of the material after LSP. In addition, particle size, PVF and particle orientation all influence the strain rate, static residual stress, static plastic strain and energy absorption during …


Numerical Investigation Of Temperature Field During Sintering Of Bioceramic Nanoparticles By Pulse Lasers, Chang Ye, Gary Cheng Apr 2015

Numerical Investigation Of Temperature Field During Sintering Of Bioceramic Nanoparticles By Pulse Lasers, Chang Ye, Gary Cheng

Dr. Chang Ye

Traditional numerical study of the temperature field of laser thermal processing is based on two assumptions: 1. heat source is a surface heat flux, and 2. uniform material properties. This method is not accurate when it comes to the laser sintering of nanoparticle integrated bioceramics coating with certain porosity. In this paper, Heat transfer (HT) model and electromagnetic (EM) model is coupled to investigate the temperature field of bioceramics nanoparticles. The heat source calculated from EM field is simultaneously input into the HT model to calculate the temperature field of the nanoparticle assembly. The interaction between the nanoparticles in the …


Laser Engineered Multilayer Coating Of Biphasic Calcium Phosphate/Titanium Nanocomposite On Metal Substrates, Martin Zhang, Chang Ye, Uriel Erasuin, Toan Huynh, Chengzhi Cai, Gary Cheng Apr 2015

Laser Engineered Multilayer Coating Of Biphasic Calcium Phosphate/Titanium Nanocomposite On Metal Substrates, Martin Zhang, Chang Ye, Uriel Erasuin, Toan Huynh, Chengzhi Cai, Gary Cheng

Dr. Chang Ye

In this work, laser coating of biphasic calcium phosphate/titanium (BCP/Ti) nanocomposite on Ti-6Al-4 V substrates was developed. A continuous wave neodymium-doped yttrium aluminium garnet (Nd:YAG) laser was used to form a robust multilayer of BCP/Ti nanocomposite starting from hydroxyapatite and titanium nanoparticles. In this process, low power coating is realized because of the strong laser−nanoparticle interaction and good sinterability of nanosized titanium. To guide the optimization of laser processing conditions for the coating process, a multiphysics model coupling electromagnetic module with heat transfer module was developed. This model was validated by laser coating experiments. Important features of the coated samples, …


Nanoparticles Embedding Into Metallic Materials By Laser Direct Irradiation, Dong Lin, Chang Ye, Yiliang Liao, C. Liu, Gary Cheng Apr 2015

Nanoparticles Embedding Into Metallic Materials By Laser Direct Irradiation, Dong Lin, Chang Ye, Yiliang Liao, C. Liu, Gary Cheng

Dr. Chang Ye

We report a method to half-embed nanoparticles into metallic materials. Transparent and opaque nanoparticle (laser wavelength 1064 nm) were both successfully half-embedded (partial part of nanoparticles embedded into matrix while other parts still stay above the matrix) into metallic materials. Nanoparticles were coated on sample surface by dip coating before laser irradiation. After laser irradiation of different pulses and laser fluencies, nanoparticles were embedded into metal. The mechanism and process of embedding were investigated.


Understanding The Influence Of Copper Nanoparticles On Thermal Characteristics And Microstructural Development Of A Tin-Silver Solder, D. Lin, T. Srivatsan, Guo-Xiang Wang, R. Kovacevic Apr 2015

Understanding The Influence Of Copper Nanoparticles On Thermal Characteristics And Microstructural Development Of A Tin-Silver Solder, D. Lin, T. Srivatsan, Guo-Xiang Wang, R. Kovacevic

Dr. Guo-Xiang Wang

This paper presents and discusses issues relevant to solidification of a chosen lead-free solder, the eutectic Sn-3.5%Ag, and its composite counterparts. Direct temperature recordings for the no-clean solder paste during the simulated reflow process revealed a significant amount of undercooling to occur prior to the initiation of solidification of the eutectic Sn-3.5%Ag solder, which is 6.5 °C, and for the composite counterparts, it is dependent on the percentage of copper nanopowder. Temperature recordings revealed the same temperature level of 221 °C for both melting (from solid to liquid) and final solidification (after recalescence) of the Sn-3.5%Ag solder. Addition of copper …


Nanoparticles For Stem-Cell Engineering, Esmaiel Jabbari Mar 2015

Nanoparticles For Stem-Cell Engineering, Esmaiel Jabbari

Esmaiel Jabbari

No abstract provided.


Effect Of Grafting Bmp2-Derived Peptide To Nanoparticles On Osteogenic And Vasculogenic Expression Of Stromal Cells, Angel Mercado, Xiaoming Yang, Xuezhong He, Esmaiel Jabbari Jan 2015

Effect Of Grafting Bmp2-Derived Peptide To Nanoparticles On Osteogenic And Vasculogenic Expression Of Stromal Cells, Angel Mercado, Xiaoming Yang, Xuezhong He, Esmaiel Jabbari

Esmaiel Jabbari

No abstract provided.


Targeted Delivery With Peptidomimetic Conjugated Self-Assembled Nanoparticles, Esmaiel Jabbari Jan 2015

Targeted Delivery With Peptidomimetic Conjugated Self-Assembled Nanoparticles, Esmaiel Jabbari

Esmaiel Jabbari

No abstract provided.


Carbon Nanotubes On Carbon Nanofibers: A Novel Structure Based On Electrospun Polymer Nanofibers, H. Hou, Darrell Reneker Jul 2014

Carbon Nanotubes On Carbon Nanofibers: A Novel Structure Based On Electrospun Polymer Nanofibers, H. Hou, Darrell Reneker

Darrell Hyson Reneker

No abstract provided.


Tuning The Magnetostructural Phase Transition In Ferh Nanocomposites, Radhika Barua, Xiujuan Jiang, Felix Jiménez-Villacorta, J. Shield, D. Heiman, L. Lewis Aug 2013

Tuning The Magnetostructural Phase Transition In Ferh Nanocomposites, Radhika Barua, Xiujuan Jiang, Felix Jiménez-Villacorta, J. Shield, D. Heiman, L. Lewis

Donald Heiman

Effects of nanostructuring on the magnetostructural response of the near-equiatomic FeRh phase were investigated in nanocomposite materials synthesized by rapid solidification and subsequent annealing of an alloy of nominal atomic composition (FeRh)5Cu95. Transmission electron microscopy studies confirm attainment of a phase-separated system of nanoscaled (∼10–15 nm diameter) precipitates, consistent with FeRh embedded in a Cu matrix. These nanoprecipitates are crystallographically aligned with the coarse-grained Cu matrix and possess an L10-type (CuAu 1) structure, in contrast to the B2 (CsCl)-type structure of bulk FeRh. It is proposed that the face-centered cubic crystal structure of the …


Large Coercivity In Nanostructured Rare-Earth-Free Mnₓga Films, Don Heiman, Tom Nummy, Steve Bennett, Tom Cardinal Oct 2012

Large Coercivity In Nanostructured Rare-Earth-Free Mnₓga Films, Don Heiman, Tom Nummy, Steve Bennett, Tom Cardinal

Donald Heiman

The magnetic hysteresis of MnₓGa films exhibit remarkably large coercive fields as high as μₒHC=2.5 T when fabricated with nanoscale particles of a suitable size and orientation. This coercivity is an order of magnitude larger than in well-ordered epitaxial film counterparts and bulk materials. The enhanced coercivity is attributed to the combination of large magnetocrystalline anisotropy and ~50-100 nm size nanoparticles. The large coercivity is also replicated in the electrical properties through the anomalous Hall effect. The magnitude of the coercivity approaches that found in rare-earth magnets, making them attractive for rare-earth-free magnet applications.


A Benchmark Study On The Thermal Conductivity Of Nanofluids, Jacopo Buongiorno, David Venerus, Naveen Prabhat, Thomas Mckrell, Jessica Townsend, Rebecca Christianson, Yuriv Tolmachev, Pawel Keblinski, Lin-Wen Hu, Jorge Alvarado, In Cheol Bang, Sandra Bishnoi, Marco Bonetti, Frank Botz, Anselmo Cecere, Yun Chang, Gang Chen, Haisheng Chen, Sung Jae Chung, Minking Chyu, Sarit Das, Roberto Di Paola, Yulong Ding, Frank Dubois, Grzegorz Dzido, Jacob Eapen, Werner Escher, Denis Funfschilling, Quentin Galand, Jinwei Gao, Patricia Gharagozloo, Kenneth Goodson, Jorge Gutierrez, Haiping Hong, Mark Horton, Kyo Sik Hwang, Carlo Iorio, Seok Pil Jang, Andrzej Jarzebski, Yiran Jiang, Stephan Kabelac, Liwen Jin, Aravind Kamath, Mark Kedzierski, Lim Geok Kieng, Chongyoup Kim, Ji-Hyun Kim, Seokwon Kim, Seung Hyun Lee, Kai Choong Leong, Indranil Manna, Bruno Michel, Rui Ni, Hrishikesh Patel, John Philip, Dimos Poulikakos, Cecil Reynaud, Raffaele Savino, Pawan Singh, Pengxiang Song, Thirumalachari Sundararajan, Elena Timofeeva, Todd Tritcak, Aleksandr Turanov, Stefan Van Vaerenbergh, Dongsheng Wen, Sanjeeva Witharana, Chun Yang, Wei-Hsun Yeh, Xiao-Zheng Zhao, Sheng-Qi Zhou Dec 2011

A Benchmark Study On The Thermal Conductivity Of Nanofluids, Jacopo Buongiorno, David Venerus, Naveen Prabhat, Thomas Mckrell, Jessica Townsend, Rebecca Christianson, Yuriv Tolmachev, Pawel Keblinski, Lin-Wen Hu, Jorge Alvarado, In Cheol Bang, Sandra Bishnoi, Marco Bonetti, Frank Botz, Anselmo Cecere, Yun Chang, Gang Chen, Haisheng Chen, Sung Jae Chung, Minking Chyu, Sarit Das, Roberto Di Paola, Yulong Ding, Frank Dubois, Grzegorz Dzido, Jacob Eapen, Werner Escher, Denis Funfschilling, Quentin Galand, Jinwei Gao, Patricia Gharagozloo, Kenneth Goodson, Jorge Gutierrez, Haiping Hong, Mark Horton, Kyo Sik Hwang, Carlo Iorio, Seok Pil Jang, Andrzej Jarzebski, Yiran Jiang, Stephan Kabelac, Liwen Jin, Aravind Kamath, Mark Kedzierski, Lim Geok Kieng, Chongyoup Kim, Ji-Hyun Kim, Seokwon Kim, Seung Hyun Lee, Kai Choong Leong, Indranil Manna, Bruno Michel, Rui Ni, Hrishikesh Patel, John Philip, Dimos Poulikakos, Cecil Reynaud, Raffaele Savino, Pawan Singh, Pengxiang Song, Thirumalachari Sundararajan, Elena Timofeeva, Todd Tritcak, Aleksandr Turanov, Stefan Van Vaerenbergh, Dongsheng Wen, Sanjeeva Witharana, Chun Yang, Wei-Hsun Yeh, Xiao-Zheng Zhao, Sheng-Qi Zhou

Rebecca J. Christianson

This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or “nanofluids,” was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (±10% or less) about …


Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet Dokmeci, Kai-Tak Wan Jun 2011

Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet Dokmeci, Kai-Tak Wan

Mehmet R. Dokmeci

We report a technique to characterize adhesion of monolayered/multilayered graphene sheets on silicon wafer. Nanoparticles trapped at graphene-silicon interface act as point wedges to support axisymmetric blisters. Local adhesion strength is found by measuring the particle height and blister radius using a scanning electron microscope. Adhesion energy of the typical graphene-silicon interface is measured to be 151±28 mJ/m2. The proposed method and our measurements provide insights in fabrication and reliability of microelectromechanical/nanoelectromechanical systems.