Note On The Rate And Energy Efficiency Limits For Additive Manufacturing,
2017
Massachusetts Institute of Technology
Note On The Rate And Energy Efficiency Limits For Additive Manufacturing, Timothy Gutowski, Sheng Jiang, Daniel Cooper, Gero Corman, Michael Hausmann, Jan-Anders Manson, Timo Schudeleit, Konrad Wegener, Matias Sabelle, Jorge Ramos-Grez, Dusan P. Sekulic
Mechanical Engineering Faculty Publications
We review the process rates and energy intensities of various additive processing technologies and focus on recent progress in improving these metrics for laser powder bed fusion processing of metals, and filament and pellet extrusion processing of polymers and composites. Over the last decade, observed progress in raw build rates has been quite substantial, with laser metal processes improving by about 1 order of magnitude, and polymer extrusion processes by more than 2 orders of magnitude. We develop simple heat transfer models that explain these improvements, point to other possible strategies for improvement, and highlight rate limits. We observe a …
Interplay Of Quantum Size Effect, Anisotropy And Surface Stress Shapes The Instability Of Thin Metal Films,
2017
Western Kentucky University
Interplay Of Quantum Size Effect, Anisotropy And Surface Stress Shapes The Instability Of Thin Metal Films, Mikhail Khenner
Mathematics Faculty Publications
Morphological instability of a planar surface ([111], [011], or [001]) of an ultra-thin metal film is studied in a parameter space formed by three major effects (the quantum size effect, the surface energy anisotropy and the surface stress) that influence a film dewetting. The analysis is based on the extended Mullins equation, where the effects are cast as functions of the film thickness. The formulation of the quantum size effect (Z. Zhang et al., PRL 80, 5381 (1998)) includes the oscillation of the surface energy with thickness caused by electrons confinement. By systematically comparing the effects, their contributions into the …
Design And Fabrication Of Functionally Graded Material From Ti To Γ-Tial By Laser Metal Deposition,
2017
Missouri University of Science and Technology
Design And Fabrication Of Functionally Graded Material From Ti To Γ-Tial By Laser Metal Deposition, Xueyang Chen, Lei Yan, Joseph William Newkirk, Frank W. Liou
Materials Science and Engineering Faculty Research & Creative Works
Functionally graded material (FGM) is one kind of advanced material characterized by a gradual change in properties as the position varies. The spatial variation of compositional and microstructure over volume is aimed to control corresponding functional properties. In this research, when 100% γ-TiAl was directly deposited on pure Ti substrate, cracks were formed within the γ-TiAl layer. Then a six-layer crack-free functionally graded material of Ti/TiAl was designed and fabricated by laser metal deposition (LMD) method, with composition changing from pure Ti on one side to 100% γ-TiAl on the other side. The fabricated FGM was characterized for material properties …
Influence Of Gage Length On Miniature Tensile Characterization Of Powder Bed Fabricated 304l Stainless Steel,
2017
Missouri University of Science and Technology
Influence Of Gage Length On Miniature Tensile Characterization Of Powder Bed Fabricated 304l Stainless Steel, Sreekar Karnati, Jack L. Hoerchler, Frank W. Liou, Joseph William Newkirk
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Miniature tensile specimens with varying aspect ratios were fabricated from 304L stainless steel (SS) made using powder bed additive manufacturing (AM) process. The tensile characteristics measured from these specimens were analyzed to assess the impact of gage length. The study found no impact upon varying gage length on yield and ultimate strength measurements. However, a significant impact was observed on strain measurements. This data was also used to perform Weibull statistics to estimate the stochastic performance of the material. Fractography was performed to visually identify the types of flaws. A comparative study with specimens fabricated from cold rolled annealed 304 …
Characterization Of Heat-Affected Powder Generated During Selective Laser Melting Of 304l Stainless Steel Powder,
2017
Missouri University of Science and Technology
Characterization Of Heat-Affected Powder Generated During Selective Laser Melting Of 304l Stainless Steel Powder, Austin T. Sutton, Caitlin S. Kriewall, Ming-Chuan Leu, Joseph William Newkirk
Mechanical and Aerospace Engineering Faculty Research & Creative Works
The selective laser melting (SLM) process is an Additive Manufacturing (AM) technique that uses a laser to fuse successive layers of powder into near fully dense components. Due to the large energy input from the laser during processing, vaporization and instabilities in the melt pool occur causing the formation of condensate and laser spatter, collectively known as heat-affected powder. Since heat-affected powder settles into the powder bed, the properties of the unconsolidated powder may be altered compromising its reusability. In this study, characterization of 304L heat-affected powder was performed through particle size distribution measurements, x-ray diffraction, metallography, energy-dispersive spectroscopy mapping, …
Analysis Of Variable Insensitive Friction Stir Welding Parameters,
2017
University of New Orleans
Analysis Of Variable Insensitive Friction Stir Welding Parameters, Robert L. Marrero Jr
LSU New Orleans Theses and Dissertations
Friction Stir Welding (FSW) was used to perform a Design of Experiment (DOE) to determine the welding parameters effects on yielding consistent mechanical properties across the length of the weld. The travel speed was varied across set forge force and RPM conditions, to find a dataset that will yield consistent mechanical properties independent of the travel speed. Six different welds were completed on two different aluminum panels, the advancing side being Aluminum alloy 2195-T8 at a thickness of .350”, with the retreating side being Aluminum alloy 2219-T851 with a gauge thickness of .360”. A Left-hand Right-hand self-reacting pin tool was …
Studying Chromium And Nickel Equivalency To Identify Viable Additive Manufacturing Stainless Steel Chemistries,
2017
Missouri University of Science and Technology
Studying Chromium And Nickel Equivalency To Identify Viable Additive Manufacturing Stainless Steel Chemistries, Zachary T. Hilton, Joseph William Newkirk, Ronald J. O'Malley
Materials Science and Engineering Faculty Research & Creative Works
Chromium and nickel equivalency modeling has long been used in welding to determine the weldability of steel chemistries. A study was conducted to determine the applicability of Cr-Ni modeling to the additive manufacturing process. Many AM methods involve rapid solidification of small melt pools, similar to welding. Chemistries with varying Cr/Ni ratios were selected for use in a selective laser melting process and modeled using known models. Initial results indicate that the standard "safe welding zone" may not directly apply to additive manufacturing. The capability to build with chemistries outside the weldability “safe zone” could result in improved and varied …
Irradiation-Induced Nanocluster Evolution,
2017
William Penn University
Irradiation-Induced Nanocluster Evolution, Didier Ishimwe, Matthew J. Swenson, Janelle P. Wharry
The Summer Undergraduate Research Fellowship (SURF) Symposium
Oxide dispersion strengthened steel (ODS) and commercial ferritic-martensitic (F-M) alloys are widely accepted candidate structural materials for designing advanced nuclear reactors. Nanoclusters embedded in the steel matrix are key microstructural features of both alloy types. Irradiation from nuclear fusion and fission affects the morphology of these nanoparticles, altering the performance of the alloys and potentially decreasing their usable lifetime. Thus, it is important to understand the effect of irradiation on these nanoparticles in order to predict long-term nuclear reactor performance. It was found that the evolution of nanoclusters in each material is different depending on the experimental irradiation parameters. The …
Spectroscopic Contrast Of Diarylethene Molecules On Octanethiol Monolayer,
2017
Physics of Nanodevices, Zernike Institute for Advanced Materials, University of Groningen, Groningen, NL-9747 AG, The Netherlands
Spectroscopic Contrast Of Diarylethene Molecules On Octanethiol Monolayer, Arramel Arramel, Tibor Kudernac, Nathalie Katsonis, Bernard Lucas Feringa, Bart Jan Van Wees
Makara Journal of Technology
We present a systematic scanning tunneling microscopy (STM) study of bias-dependent imaging of disulfur diarylethene (2S-DE) molecules on octanethiol (C8) monolayer at room temperature. In a rigid confinement of the C8 matrix, we did not observe any significant variation in the appearance of the 2S-DE. On the contrary, a reversal in the apparent height of the 2S-DE was present when the molecule was situated on a gold vacancy island. We attributed this finding to the presence of a new electronic state that became accessible for a tunneling event. In addition, the C8 surface structure underwent a reversible phase transformation from …
Residual Stress Measurements On The Tig Weld Joint Of 57fe15cr25ni Austenitic Steel For Structural Material Applications By Means X-Ray Diffraction Techniques,
2017
Center for Science and Technology of Advanced Materials, National Nuclear Energy Agency (BATAN), Puspiptek Serpong, South Tangerang 15314, Indonesia
Residual Stress Measurements On The Tig Weld Joint Of 57fe15cr25ni Austenitic Steel For Structural Material Applications By Means X-Ray Diffraction Techniques, Parikin Parikin, Agus Hadi Ismoyo, Riza Iskandar, Arbi Dimyati
Makara Journal of Technology
Measurements of residual stress on the 57Fe25Cr15Ni steel plate with no-filler TIG-welding process were carried out. This work was conducted to determine the nature of weld ability in synthesized steel. The bulks were formed in a dimension of 30x20x7 mm3 to ease data retrieval. Results show that the largest residual stress occurred in the weld metal area, amounting to 82.40 MPa with lattice stretching of 0.18%. Conversely, the values decreased to 65.92 MPa and a stretch of 0.14% in the HAZ area. This residual stress is a tensile stress that can reduce the mechanical strength of the material since it …
An Efficient Palladium-Thiourea Catalysed Heck Cross-Coupling Reaction For Molecular Electronic Interest,
2017
School of Fundamental Science, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia
An Efficient Palladium-Thiourea Catalysed Heck Cross-Coupling Reaction For Molecular Electronic Interest, Wan M. Khairul, Mohd Shahrul Shahmi Md Shariff, Rafizah Rahamathullah, Adibah Izzati Daud, Mustaffa Shamsuddin, Siti Kamilah Che Soh
Makara Journal of Technology
The synthesis and utilization of C-C bonds formation are concerned about the key steps for the building of several conducting molecular electronics involving many asymmetric catalysts approached, which is an essential task that most researchers would ignore in preparing these materials to enhance the production yield of cross-coupling materials. Despite the enormous progress, there still remains a great demand for economic and practicable cross-coupling processes involving ultra-low catalyst loadings with high turnover numbers due to the employment of conventional metal catalyst. Thus, there has been an excessive interest to cultivate non-phosphine palladium catalysts for excellent achievement of activity, stability, and …
A Study On Dielectric Properties Of The Cellulose Derivative-Nh4br-Glycerol- Based The Solid Polymer Electrolyte System,
2017
Advanced Materials Cluster, Faculty of Industrial Sciences & Technology, Universiti Malaysia Pahang, Lebuhraya Tun Razak, Gambang 26300, Kuantan, Pahang, Malaysia
A Study On Dielectric Properties Of The Cellulose Derivative-Nh4br-Glycerol- Based The Solid Polymer Electrolyte System, Nur Muhitul Jalilah Rasali, Saifful Kamaluddin Muzakir, Ahmad Salihin Samsudin
Makara Journal of Technology
The characterization of biopolymer-based solid polymer electrolytes (SPEs) has been carried out in this present work. Cellulose derivative was chosen due to its superior physical attributes. In this work, NH4Br-doped glycerol plasticized carboxyl methylcellulose-based SPEs were successfully prepared via the solution casting method. The conductivity and dielectric properties of the prepared films were investigated using the impedance analysis which presented ~1.91×10-3 Scm-1 (with addition of 6 wt% of glycerol). In addition, the studied SPE system shows a non-Debye behaviour without a single relaxation time. The findings of the research indicate that the complexes of NH4Br and glycerol in the cellulose …
Urban Drainage Management And Flood Control Improvement Using The Duflow Case Study: Aur Sub Catchment, Palembang, South Sumatra, Indonesia,
2017
Department of Land and Water Development, Water Science and Engineering, UNESCO IHE, Westvest 7 2611 AX Delft, The Netherlands
Urban Drainage Management And Flood Control Improvement Using The Duflow Case Study: Aur Sub Catchment, Palembang, South Sumatra, Indonesia, Charlotte De Fraiture, Robiyanto Hendro Susanto, F.X. Suryadi, Harrini Mutiara Hapsari Wahyu
Makara Journal of Technology
Urban flooding often times staggers the livelihood in an urban area, which most likely happens in the lowland urban area. Therefore, the existing urban drainage system should be improved in order to tackle the upcoming urban flooding events, which are more than likely to be more devastating than those in the previous years. The research location is in Palembang, Sumatra, Indonesia, where 30% of its urban part is a lowland area. The selected Aur Sub Catchment is located in Silaberanti. The main objective of this research is to improve the current drainage system in order to achieve the optimal design …
Ethanol Purification Using Activated Natural Zeolite,
2017
Department of Chemical Engineering, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia
Ethanol Purification Using Activated Natural Zeolite, Chandra Wahyu Purnomo, Nelliza Putri, Indra Perdana, Hirofumi Hinode
Makara Journal of Technology
Bio ethanol is one of the potential fuels in the future. However, ethanol in water mixture has an azeotropic concentration of 95.6 wt. %, which makes it difficult to purify further. The common method of purification is by using an azeotropic distillation column, which requires an intensive energy and an addition of specific solvent. In this study, ethanol purification is done using an adsorption column packed with zeolite Raschig rings. The natural zeolite ring was modified beforehand using the NaOH solution to enhance the material’s water adsorption performance. The ethanol purity can reach more than 99% with the modified zeolite …
Physical And Mechanical Properties Of Palm Kernel Oil-Based Polyester Polyurethane/Multi-Walled Carbon Nanotube Composites,
2017
School of Fundamental Science, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia
Physical And Mechanical Properties Of Palm Kernel Oil-Based Polyester Polyurethane/Multi-Walled Carbon Nanotube Composites, Khairul Anuar Mat Amin, Muhammad Alif Zailani, Nurul Nabilah Zulkifli, Khairiah Haji Badri
Makara Journal of Technology
In this study, polyurethane (PU) films from palm kernel oil-based polyester (PKO-p) incorporated multi-walled carbon nanotubes (MWNTs) are prepared via a evaporative casting method. Nanoparticle fluid dispersions containing 0.02%, 0.03%, and 0.05% wt. of MWNTs are added into PKO-p based resin and mixed by digital probe sonicator for 30 min followed by mixing with isocyanate to produce PU-MWNTs composite films. The mechanical properties, swelling, water vapour transmission rate (WVTR) and conductivity of the PU-MWNTs composite films are examined. Results show that the toughness (T) or flexibility, the tensile strength (TS), and Young’s modulus (YM) values of PU-MWNTs composite films increase …
Personality Trait Based Intervention For Workplace Accident Prevention,
2017
Faculty of Industrial Technology, Institut Teknologi Bandung, Bandung 40132, Indonesia
Personality Trait Based Intervention For Workplace Accident Prevention, Yassierli Yassierli, Nurhayati Nurhayati, Marisa Anatasia, Shamsul Bahri
Makara Journal of Technology
Previous research has suggested that some traits may be useful as the predictors of risk behaviours behaviors. Therefore, personality traits seem to play a role in accident involvement. The purpose of this study is was to explore the relationship between the personality traits based on the Big Five Inventory (BFI) and worker accident experiences in order to elaborate personality traits based intervention for workplace accident prevention. A cross cross-sectional study was conducted among 173 workers in a cement company using a set of questionnaires consisting of respondents’ characteristics, BFI, and self-reported accident experience. The correlations were computed using Goodman Kruskal’s …
Analysis And Modeling Of The Growth Of Intermetallic Compounds In Aluminum–Steel Joints,
2017
Lanzhou University of Technology, China
Analysis And Modeling Of The Growth Of Intermetallic Compounds In Aluminum–Steel Joints, Gang Zhang, Manjiao Chen, Yu Shi, Jiankang Huang, Fuqian Yang
Chemical and Materials Engineering Faculty Publications
In this work, we experimentally and numerically studied the microstructures and growth of intermetallic compounds (IMCs) formed in Al–Fe (aluminum–steel) joints welded by a pulsed double electrode gas metal arc welding (DE-GMAW)-brazing method. The IMCs consist of Fe2Al5 and FeAl3, with Fe2Al5 being the main compound in the joints. The thickness of an IMC layer increases with an increase of the welding current (heat input) into the base metal. EBSD measurement suggests that the preferred crystal orientation of the Fe2Al5 IMC likely provides the necessary path for Al atoms …
The Mechanism Of Radiation-Induced Nanocluster Evolution In Oxide Dispersion Strengthened And Ferritic-Martensitic Alloys,
2017
Boise State University
The Mechanism Of Radiation-Induced Nanocluster Evolution In Oxide Dispersion Strengthened And Ferritic-Martensitic Alloys, Matthew John Swenson
Boise State University Theses and Dissertations
The objective of this study is to evaluate the mechanism of irradiation-induced nanoparticle evolution in a model Fe-9%Cr oxide dispersion strengthened steel and commercial ferritic-martensitic alloys HCM12A and HT9. Each alloy is irradiated with Fe2+ ions, protons, or neutrons to doses ranging from 1-100 displacements per atoms at 500°C. The morphology of nanoclusters are characterized using atom probe tomography. The evolution of clusters in each alloy are notably different with each irradiating particle, and the competing effects of ballistic dissolution and radiation-enhanced, diffusion-driven growth are attributed to the respective differences in cluster evolution. A phase evolution model, originally theorized …
Characterization Of Slm Printed 316l Stainless Steel And Investigation Of Microlattice Geometry,
2017
California Polytechnic State University, San Luis Obispo
Characterization Of Slm Printed 316l Stainless Steel And Investigation Of Microlattice Geometry, Finley H. Marbury
Materials Engineering
The goal of this project was firstly to characterize Cal Poly’s SLM printed 316L stainless steel. SEM analysis showed Cal Poly’s as-printed 316L material to have a cellular dendritic microstructure containing mostly austenite and a small amount of δ-ferrite. After being heat treated to eliminate warp, its yeild and ultimate tensile strength were on par with the literature, however higher modulus and lower elongation were observed. XRD analysis confirmed residual stresses in the material, and that grains are preferentially oriented in both heat treated and non heat treated samples. The amount of porosity in the material was found to be …
Characterization Of The 15-5 Stainless Steel Electric Discharge Machining Recast Layer,
2017
California Polytechnic State University, San Luis Obispo
Characterization Of The 15-5 Stainless Steel Electric Discharge Machining Recast Layer, Julian R. Lohser, Rhys W. Gilmore
Materials Engineering
Electric discharge machining (EDM) is a non-conventional machining process that is used for tough, hard materials or materials that require no tool force. Wire EDM produces a recast layer and heat-affected zone as a result of rapid melting and quenching at the surface of the cut. A secondary machining operation has been required to remove this layer. Previous estimates of the depth of the recast layer are likely too conservative due to improvements in the technology; therefore, the goal of this study is to characterize and more accurately investigate the size of the layer. Two EDM machine parameters, voltage and …
