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

Engineering Commons

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

Articles 1 - 17 of 17

Full-Text Articles in Engineering

Electroshock Treatment Dependent Microstructural Evolution And Mechanical Properties Of Near-Β Titanium Alloy Manufactured By Directed Energy Deposition, Haojie Guo, Pu Liu, Xunpeng Qin, Yanli Song, Dongsheng Qian, Lechun Xie, Liqiang Wang, Lai-Chang Zhang, Lin Hua Dec 2021

Electroshock Treatment Dependent Microstructural Evolution And Mechanical Properties Of Near-Β Titanium Alloy Manufactured By Directed Energy Deposition, Haojie Guo, Pu Liu, Xunpeng Qin, Yanli Song, Dongsheng Qian, Lechun Xie, Liqiang Wang, Lai-Chang Zhang, Lin Hua

Research outputs 2014 to 2021

Effects of electroshock treatment (EST) on the microstructural evolution and mechanical properties of near-β titanium alloy (Ti-55531) formed by directed energy deposition (DED) was studied in this work. With the increase in EST time, the average hardness of specimen decreased from 426 HV to 316 HV, and the fracture strain increased significantly, which was attributed to the uniform dispersion of α phase along grain boundaries and inside the β grains. After EST, the texture intensity decreased in terms of the orientation distribution function (ODF), which was ascribed to the redistribution of α phase. Moreover, more atomic vacancies and lattice distortion …


Topological Design Of Pentamode Lattice Metamaterials Using A Ground Structure Method, Zuyu Li, Zhen Luo, Lai-Chang Zhang, Chun-Hui Wang Jan 2021

Topological Design Of Pentamode Lattice Metamaterials Using A Ground Structure Method, Zuyu Li, Zhen Luo, Lai-Chang Zhang, Chun-Hui Wang

Research outputs 2014 to 2021

Pentamode metamaterials are a new class of artificially engineering three-dimensional lattice composites. There exist a few types of pentamode metamaterials that are dominated by ad hoc design motifs, while a systematic design approach is still missing. This paper will present an efficient topological optimization methodology to discover a series of novel pentamode lattice microarchitectures over a range of effective material properties. Firstly, the necessary and sufficient condition that is required for elasticity constants of pentamode micro lattices with at least elastically orthotropic symmetry is derived. Secondly, a general mathematical formulation for design optimization of such pentamode micro lattices is developed. …


Corrosion Behavior And Characteristics Of Passive Films Of Laser Powder Bed Fusion Produced Ti-6al-4v In Dynamic Hank’S Solution, Liang-Yu Chen, Hong-Yue Zhang, Chuanbo Zheng, Hong-Yu Yang, Peng Qin, Cuihua Zhao, Sheng Lu, Shun-Xing Liang, Linjiang Chai, Lai-Chang Zhang Jan 2021

Corrosion Behavior And Characteristics Of Passive Films Of Laser Powder Bed Fusion Produced Ti-6al-4v In Dynamic Hank’S Solution, Liang-Yu Chen, Hong-Yue Zhang, Chuanbo Zheng, Hong-Yu Yang, Peng Qin, Cuihua Zhao, Sheng Lu, Shun-Xing Liang, Linjiang Chai, Lai-Chang Zhang

Research outputs 2014 to 2021

The corrosion behavior of laser powder bed fusion produced (L-PBF-produced) titanium alloys involving flowing body fluid is still unclear. Therefore, this work investigates in vitro corrosion behavior and the characteristics of passive films formed on L-PBF-produced Ti–6Al–4V in both static and dynamic Hank’s solutions. Electrochemical measurements, immersion tests, X-ray photoelectron spectroscopy and scanning electron microscopy were conducted. In comparison to the L-PBF-produced Ti–6Al–4V in static Hank’s solution, the samples showed lower charge transfer resistance and higher passivation current density (anodic current density as well) in dynamic Hank’s solution. Meanwhile, a more apparent deposition of apatite and hydroxyapatite is found on …


Relationship Between Pressure And Output Parameters In Belt Grinding Of Steels And Nickel Alloy, Nelli V. Syreyshchikova, Danil Y. Pimenov, Munish K. Gupta, Krzysztof Nadolny, Khaled Giasin, Muhammad Aamir, Shubham Sharma Jan 2021

Relationship Between Pressure And Output Parameters In Belt Grinding Of Steels And Nickel Alloy, Nelli V. Syreyshchikova, Danil Y. Pimenov, Munish K. Gupta, Krzysztof Nadolny, Khaled Giasin, Muhammad Aamir, Shubham Sharma

Research outputs 2014 to 2021

Belt grinding of flat surfaces of typical parts made of steel and alloys, such as grooves, shoulders, ends, and long workpieces, is a good alternative to milling. Several factors can influence the belt grinding process of flat surfaces of metals, such as cutting speed and pressure. In this work, the importance of pressure in the belt grinding was investigated in terms of technological and experimental aspects. The grinding experiments were performed on structural alloy steel 30KhGSN2/30KhGSNA, structural carbon steel AISI 1045, corrosion-resistant and heat-resistant stainless steel AISI 321, and heat-resistant nickel alloy KHN77TYuR. The performance of the grinding belt was …


Review On Machining Of Additively Manufactured Nickel And Titanium Alloys, Navneet Khanna, Kishan Zadafiya, Tej Patel, Yusuf Kaynak, Rizwan Abdul, Rahman Rashid, Ana Vafadar Jan 2021

Review On Machining Of Additively Manufactured Nickel And Titanium Alloys, Navneet Khanna, Kishan Zadafiya, Tej Patel, Yusuf Kaynak, Rizwan Abdul, Rahman Rashid, Ana Vafadar

Research outputs 2014 to 2021

The machining of nickel and titanium-based superalloy components is very expensive and involves unusually high lead times compared with other engineering metals such as steels and aluminum. This has led to the development of most suitable additive manufacturing (AM) processes to fabricate these difficult-to-machine metals into near-net shape parts, thereby reducing the lead time and material waste, and significantly increasing productivity. Nonetheless, finish machining is still required on the AMed metal components to meet the dimensional and surface requirements of the application. Several research studies have investigated the machinability of AMed nickel and titanium alloy workpieces and have compared the …


Editorial: Hexagonal Close-Packed Metals And Alloys: Processing, Microstructure And Properties, Liang-Yu Chen, Linjiang Chai, Lai-Chang Zhang Jan 2021

Editorial: Hexagonal Close-Packed Metals And Alloys: Processing, Microstructure And Properties, Liang-Yu Chen, Linjiang Chai, Lai-Chang Zhang

Research outputs 2014 to 2021

In comparison with face-centered cubic (FCC) and body-centered cubic (BCC) metals and alloys, hexagonal close-packed (HCP) metals and alloys show distinct characteristics, such as atomic site occupation, anisotropic microstructure, and fewer slip systems, owing to their HCP lattice structure. Therefore, HCP metals and alloys have distinguished processing, microstructure, and properties. Several types of HCP metals and alloys, involving titanium, zirconium, magnesium, and so on, are extensively used in a variety of industrial and military sectors. Up to date, an increased requirement is still needed to improve the understanding of the relationships among processing, microstructures, and the resultant properties of HCP …


Spectrally-Selective Energy-Harvesting Solar Windows For Public Infrastructure Applications, Mikhail Vasiliev, Kamal Alameh, Mohammad Alam Jan 2018

Spectrally-Selective Energy-Harvesting Solar Windows For Public Infrastructure Applications, Mikhail Vasiliev, Kamal Alameh, Mohammad Alam

Research outputs 2014 to 2021

A study of photovoltaic solar window technologies is reported and it focuses on their structural features, functional materials, system development, and suitability for use in practical field applications including public infrastructures and agricultural installations. Energy generation performance characteristics are summarized and compared to theory-limit predictions. Working examples of pilot-trial solar window-based installations are described. We also report on achieving electric power outputs of about 25 Wp/m2 from clear and transparent large-area glass-based solar windows.


Leaching Of A Mongolian Chalcopyrite Concentrate, Nicholas J. Welham, Jadambaa Temuujin, Nader Setoudeh Jan 2018

Leaching Of A Mongolian Chalcopyrite Concentrate, Nicholas J. Welham, Jadambaa Temuujin, Nader Setoudeh

Research outputs 2014 to 2021

A Mongolian chalcopyrite flotation concentrate was leached using sodium hypochlorite adjusted to different pH using hydrochloric acid. It was found that using a starting pH of below 5.0 resulted in more efficient leaching. The extent of chalcopyrite leaching was determined by the concentration of sodium hypochlorite with > 40% dissolution being achieved. The residue after leaching was found to consist primarily of unreacted chalcopyrite which would be suitable for further leaching or smelting.


Influence Of Substrate Stage Temperature And Rotation Rate On The Magneto-Optical Quality Of Rf-Sputtered Bi2.1dy0.9fe3.9ga1.1o12 Garnet Thin Films, Mohammad E. Alam, Mikhail Vasiliev, Kamal Alameh Jan 2018

Influence Of Substrate Stage Temperature And Rotation Rate On The Magneto-Optical Quality Of Rf-Sputtered Bi2.1dy0.9fe3.9ga1.1o12 Garnet Thin Films, Mohammad E. Alam, Mikhail Vasiliev, Kamal Alameh

Research outputs 2014 to 2021

Highly bismuth-substituted iron garnet thin films are prepared on quartz substrates by using a radio frequency (RF) magnetron sputtering technique. We study the factors (process parameters associated with the RF magnetron sputter deposition technique) affecting the magneto-optical (MO) properties of ferrite garnet films of composition Bi2.1Dy0.9Fe3.9Ga1.1O12. All films show high MO response across the visible range of wavelengths after being annealed. In particular, the effects of substrate stage temperature and rotation rate on the various properties of films are studied. Experimental results reveal that the characteristics of garnet films of this type can be tuned and optimized for use in …


Synthesis Of Magnetic Carbon Supported Manganese Catalysts For Phenol Oxidation By Activation Of Peroxymonosulfate, Yuxian Wang, Yongbing Xie, Chunmao Chen, Xiaoguang Duan, Hongqi Sun, Shaobin Wang Dec 2017

Synthesis Of Magnetic Carbon Supported Manganese Catalysts For Phenol Oxidation By Activation Of Peroxymonosulfate, Yuxian Wang, Yongbing Xie, Chunmao Chen, Xiaoguang Duan, Hongqi Sun, Shaobin Wang

Research outputs 2014 to 2021

Magnetic core/shell nanospheres (MCS) were synthesized by a novel and facile one-step hydrothermal method. Supported manganese oxide nanoparticles (Fe3O4/C/Mn) were obtained from various methods (including redox, hydrothermal and impregnation) using MCS as the support material and potassium permanganate as the precursor of manganese oxide. The Mn/MCS catalysts were characterized by a variety of characterization techniques and the catalytic performances of Fe3O4/C/Mn nanoparticles were tested in activation of peroxymonosulfate to produce reactive radicals for phenol degradation in aqueous solutions. It was found that Fe3O4/C/Mn catalysts can be well dispersed …


High-Performance Rf-Sputtered Bi-Substituted Iron Garnet Thin Films With Almost In-Plane Magnetization, Mohammad Alam, Mikhail Vasiliev, Kamal Alameh Mar 2017

High-Performance Rf-Sputtered Bi-Substituted Iron Garnet Thin Films With Almost In-Plane Magnetization, Mohammad Alam, Mikhail Vasiliev, Kamal Alameh

Research outputs 2014 to 2021

Bismuth-substituted iron garnet thin films of high quality are prepared by using RF magnetron sputtering technique in pure argon (Ar) plasma. All the developed garnet films show high magneto-optic (MO) response after being optimally annealed across the visible range wavelengths. The garnet films display almost in-plane magnetization component with adequate Faraday rotation and relatively low optical absorption over a wide spectral range of frequencies from visible to the infrared. These garnet-type thin films demonstrate excellent MO properties together with very low coercive field of about 30 Oe, and can be used in a wide range of magneto optical applications, especially …


Determination Of Forming Ability Of High Pressure Die Casting For Zr-Based Metallic Glass, Lehua Liu, Jiang Ma, Chunyan Yu, Xiusong Huang, Liangju He, Laichang Zhang, Peijie Li, Zhiyuan Liu Jan 2017

Determination Of Forming Ability Of High Pressure Die Casting For Zr-Based Metallic Glass, Lehua Liu, Jiang Ma, Chunyan Yu, Xiusong Huang, Liangju He, Laichang Zhang, Peijie Li, Zhiyuan Liu

Research outputs 2014 to 2021

Large-sized industrial grade Zr55Cu30Ni5Al10 bulk metallic glass (BMG) was fabricated by a two-step arc-melting process and adding a trace of rare earth yttrium elements. A model to calculate critical cooling rate for forming BMG was established by considering the effect of pressure. Based on the model, the most important indicator, namely the critical size of forming BMG, for design and fabrication of BMG components by high pressure die casting (HPDC) is determined in consideration of different processing parameters, including the pressure and casting temperature. Theoretical calculation and numerical simulation indicated that increasing applied …


Gradient In Microstructure And Mechanical Property Of Selective Laser Melted Alsi10mg, Yujing Liu, Zeng Qian Liu, Y Jiang, G.W Wang, Yang Yang, Laichang Zhang Jan 2017

Gradient In Microstructure And Mechanical Property Of Selective Laser Melted Alsi10mg, Yujing Liu, Zeng Qian Liu, Y Jiang, G.W Wang, Yang Yang, Laichang Zhang

Research outputs 2014 to 2021

It is known that metal parts can be made stronger, tougher and better wear resistance by introducing gradient microstructure. This work reports the cooling rate of melt pool induced discrepancy in microstructural gradient and element distribution during selective laser melting (SLM), thereby resulting in decrease in microhardness and wear resistance from surface to inside with a range of ∼100 μm of SLM- manufactured AlSi10Mg alloy. The cooling rate in the top surface of melt pool reaches ∼ 1.44 × 106 K/s, which is much higher than that at the bottom ( ≤ 1 × 103 K/s). Such a …


Fretting Wear Behaviors Of Aluminum Cable Steel Reinforced (Acsr) Conductors In High-Voltage Transmission Line, Xingchi Ma, Lei Gao, Junxi Zhang, Laichang Zhang Jan 2017

Fretting Wear Behaviors Of Aluminum Cable Steel Reinforced (Acsr) Conductors In High-Voltage Transmission Line, Xingchi Ma, Lei Gao, Junxi Zhang, Laichang Zhang

Research outputs 2014 to 2021

This work reports the fretting wear behavior of aluminum cable steel reinforced (ACSR) conductors for use in high-voltage transmission line. Fretting wear tests of Al wires were conducted on a servo-controlled fatigue testing machine with self-made assistant apparatus, and their fretting process characteristics, friction force, wear damage, and wear surface morphology were detailed analyzed. The results show that the running regime of Al wires changes from a gross slip regime to a mixed regime more quickly as increasing contact load. With increasing amplitudes, gross slip regimes are more dominant under contact loads of lower than 30 N. The maximum friction …


Yig: Bi2o3 Nanocomposite Thin Films For Magnetooptic And Microwave Applications, M Nur-E-Alam, Mikhail Vasiliev, Kamal Alameh, Viacheslav Kotov, Victor Demidov, Dmitry Balabanov Jun 2015

Yig: Bi2o3 Nanocomposite Thin Films For Magnetooptic And Microwave Applications, M Nur-E-Alam, Mikhail Vasiliev, Kamal Alameh, Viacheslav Kotov, Victor Demidov, Dmitry Balabanov

Research outputs 2014 to 2021

Y3Fe5O12-Bi2O3 composite thin films are deposited onto Gd3Ga5O12 (GGG) substrates and their annealing crystallization regimes are optimized (in terms of both process temperatures and durations) to obtain high-quality thin film layers possessing magnetic properties attractive for a range of technological applications. The amount of bismuth oxide content introduced into these nanocomposite-type films is controlled by adjusting the RF power densities applied to both Y3Fe5O12 and Bi2O3 sputtering targets during the cosputtering deposition processes. The measured material properties of …


Bimetallic Non-Alloyed Nps For Improving The Broadband Optical Absorption Of Thin Amorphous Silicon Substrates, Chee L. Tan, Sung J. Jang, Young M. Song, Kamal Alameh, Yong T. Lee Jan 2014

Bimetallic Non-Alloyed Nps For Improving The Broadband Optical Absorption Of Thin Amorphous Silicon Substrates, Chee L. Tan, Sung J. Jang, Young M. Song, Kamal Alameh, Yong T. Lee

Research outputs 2014 to 2021

We propose the use of bimetallic non-alloyed nanoparticles (BNNPs) to improve the broadband optical absorption of thin amorphous silicon substrates. Isolated bimetallic NPs with uniform size distribution on glass and silicon are obtained by depositing a 10-nm Au film and annealing it at 600°C; this is followed by an 8-nm Ag film annealed at 400°C. We experimentally demonstrate that the deposition of gold (Au)-silver (Ag) bimetallic non-alloyed NPs (BNNPs) on a thin amorphous silicon (a-Si) film increases the film's average absorption and forward scattering over a broad spectrum, thus significantly reducing its total reflection performance. Experimental results show that Au-Ag …


Room-Temperature Spin-Polarized Organic Light-Emitting Diodes With A Single Ferromagnetic Electrode, Baofu Ding, Qunliang Song, Kamal Alameh Jan 2014

Room-Temperature Spin-Polarized Organic Light-Emitting Diodes With A Single Ferromagnetic Electrode, Baofu Ding, Qunliang Song, Kamal Alameh

Research outputs 2014 to 2021

In this paper, we demonstrate the concept of a room-temperature spin-polarized organic light-emitting diode (Spin-OLED) structure based on (i) the deposition of an ultra-thin p-type organic buffer layer on the surface of the ferromagnetic electrode of the Spin-OLED and (ii) the use of oxygen plasma treatment to modify the surface of that electrode. Experimental results demonstrate that the brightness of the developed Spin-OLED can be increased by 110% and that a magneto-electroluminescence of 12% can be attained for a 150 mT in-plane magnetic field, at room temperature. This is attributed to enhanced hole and room-temperature spin-polarized injection from the ferromagnetic …