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Selected Works

Nanoparticles

Dr. Chang Ye

Articles 1 - 6 of 6

Full-Text Articles in Mechanical 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.