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Additive manufacturing

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Articles 271 - 300 of 577

Full-Text Articles in Engineering

A Highly Conductive, Flexible, And 3d-Printable Carbon Nanotube-Elastomer Ink For Additive Bio-Manufacturing, Andy Shar, Phillip Glass, Daeha Joung Ph.D. Jan 2022

A Highly Conductive, Flexible, And 3d-Printable Carbon Nanotube-Elastomer Ink For Additive Bio-Manufacturing, Andy Shar, Phillip Glass, Daeha Joung Ph.D.

Undergraduate Research Posters

The synthesis of a highly conductive, flexible, 3D-printable, and biocompatible ink has been of great interest in the field of bio-based additive manufacturing. Various applications include ultra-sensitive, microscale tactile sensors, patient-customizable scaffolds for cardiac and nerve tissue regeneration, and flexible electrocardiogram (ECG) electrodes. Here, a novel elastomeric carbon nanocomposite is presented consisting of amino-functionalized carbon nanotubes (CNT-NH2) homogenously dispersed in a one-part room-temperature vulcanizing (RTV) silicone matrix. The use of acetone as a swelling solvent aids in electrical percolation through the elastomer matrix. CNT-NH2 ratios can be tuned to fit various needs; higher tensile strength is favored …

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Patient-Specific Cardiovascular Superelastic Niti Stents Produced By Laser Powder Bed Fusion, Valentina Finazzi, Francesca Berti, Roger J. Guillory Ii, Lorenza Petrini, Barbara Previtali, Ali Gökhan Demir Jan 2022

Patient-Specific Cardiovascular Superelastic Niti Stents Produced By Laser Powder Bed Fusion, Valentina Finazzi, Francesca Berti, Roger J. Guillory Ii, Lorenza Petrini, Barbara Previtali, Ali Gökhan Demir

Michigan Tech Publications, Part 1

To date, there is a general lack of customizability within the selection of endovascular devices for catheter-based vascular interventions. Laser powder bed fusion (LPBF) has been flexibly exploited to produce customized implants using conventional biomedical alloys for orthopedic and dental applications. Applying LPBF for cardiovascular applications, patient-specific stents can be produced with small struts (approximately 100-300 µm), variable geometries, and clinically used metals capable of superelastic behaviour at body temperature (eg. equiatomic nickel-titanium alloys, NiTi). Additionally, the growing availability and use of patient-specific 3D models provides a unique opportunity to outline the necessary manufacturing process that would be required for …

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Functionally Magnetic Gradient Copper-Nickel Material Fabricated Via Directed Energy Deposition, Vy Tran Phuong Nguyen Jan 2022

Functionally Magnetic Gradient Copper-Nickel Material Fabricated Via Directed Energy Deposition, Vy Tran Phuong Nguyen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Functionally gradient materials (FGMs) of CuSn10 and Inconel 718 were fabricated via a hybrid directed energy deposition (DED) system. The objective of the present thesis is to determine the feasibility of manufacturing CuSn10 and Inconel 718 FGMs via DED and investigate the physical and mechanical properties and the microstructures of the resulting FGMs. The physical tests comprised of conductivity and Seebeck coefficient measurements. The microstructure analysis and mechanical testing include microscopic imaging, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and hardness test. In addition, compressive strength test was performed to analyze the interface bonding behaviors.

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Characterization Of High Cycle Fatigue And Laser-Aided Machining And Polishing Of Additively Manufactured Materials, Mohammad Masud Parvez Jan 2022

Characterization Of High Cycle Fatigue And Laser-Aided Machining And Polishing Of Additively Manufactured Materials, Mohammad Masud Parvez

Doctoral Dissertations

“Additive manufacturing (AM) and laser-aided machining and polishing (LAMP) of materials are emerging manufacturing processes both for research and industrial sectors. The AM process can manufacture near-net-shape parts with complex geometries. Meanwhile, the LAMP process integrated with an AM system offers a high processing rate, minimum heat-affected zone, and easily adjustable process parameters during machining and polishing. In mechanical properties characterization of AM metals and alloys, fatigue is a vitally important test method to understand the behavior of materials in cycling loading and unloading circumstances since most mechanical failures of structures are due to fatigue. To characterize AM metal fatigue …

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Processing To Enable Direct-Write Additive Manufacturing Of Ceramics And Ceramic Composites, Austin Martin Jan 2022

Processing To Enable Direct-Write Additive Manufacturing Of Ceramics And Ceramic Composites, Austin Martin

Doctoral Dissertations

"This research focuses on the processing of novel feedstocks for and during direct-write additive manufacturing (AM), specifically the direct ink writing (DIW) and Ceramic On-Demand Extrusion (CODE) manufacturing processes, in order to produce ceramic and ceramic-based composite components. Strongly dispersed, concentrated (φ = 0.42), nanoparticle (d50 ~0.3 µm), zirconia (ZrO2) pastes were used to print densely filled, large continuous volume (≳ 1 cm3) ceramic components. An elastic shear modulus (G’) of 56,000 Pa and yield stresses between 6 and 10 Pa allowed for printed components of 34.5 mm in height over 115 layers without slumping …

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Plasma Spheroidization Of Gas-Atomized 304l Stainless Steel Powder For Laser Powder Bed Fusion Process, M. Hossein Sehhat, Austin T. Sutton, Chia-Hung Hung, Ben Brown, Ronald J. O'Malley, Jonghyun Park, Ming-Chuan Leu Jan 2022

Plasma Spheroidization Of Gas-Atomized 304l Stainless Steel Powder For Laser Powder Bed Fusion Process, M. Hossein Sehhat, Austin T. Sutton, Chia-Hung Hung, Ben Brown, Ronald J. O'Malley, Jonghyun Park, Ming-Chuan Leu

PSMRC Faculty Research

Particles of AISI 304L stainless steel powder were spheroidized by the induction plasma spheroidization process (TekSphero-15 spheroidization system) to assess the effects of the spheroidization process on powder and part properties. The morphology of both as-received and spheroidized powders was characterized by measuring particle size and shape distribution. The chemistry of powders was studied using inductively coupled plasma optical emission spectroscopy for evaluation of composing elements, and the powder’s microstructure was assessed by X-ray diffraction for phase identification and by electron backscattered diffraction patterns for crystallography characterization. The Revolution Powder Analyzer was used to quantify powder flowability. The mechanical properties …

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3d Printing Technology In Aerospace Industry – A Review, Mohammad Suhel Karkun, Sathish Dharmalingam Jan 2022

3d Printing Technology In Aerospace Industry – A Review, Mohammad Suhel Karkun, Sathish Dharmalingam

International Journal of Aviation, Aeronautics, and Aerospace

In the modern era, several new technologies are being developed for the most convenient and easy usage of materials. Due to its effortless and quick usage properties, 3D printing technology has a vast application range nowadays in different fields. The application of 3D printing technology in the aerospace industry has been developed in the past few decades, but now it has been enhanced to a new level. 3D printing technology now has several applications in the aeronautical and space sectors. Soon, 3D printing technology will be used for building habitations on other planets and for the printing of spacecraft and …

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Towards An Instant Structure-Property Prediction Quality Control Tool For Additive Manufactured Steel Using A Crystal Plasticity Trained Deep Learning Surrogate, Yuhui Tu, Zhongzhou Liu, Luiz Carneiro, Caitriona M. Ryan, Andrew C. Parnell, Sean B. Leen Jan 2022

Towards An Instant Structure-Property Prediction Quality Control Tool For Additive Manufactured Steel Using A Crystal Plasticity Trained Deep Learning Surrogate, Yuhui Tu, Zhongzhou Liu, Luiz Carneiro, Caitriona M. Ryan, Andrew C. Parnell, Sean B. Leen

Research Collection School Of Computing and Information Systems

The ability to conduct in-situ real-time process-structure-property checks has the potential to overcome process and material uncertainties, which are key obstacles to improved uptake of metal powder bed fusion in industry. Efforts are underway for live process monitoring such as thermal and image-based data gathering for every layer printed. Current crystal plasticity finite element (CPFE) modelling is capable of predicting the associated strength based on a microstructural image and material data but is computationally expensive. This work utilizes a large database of input–output samples from CPFE modelling to develop a trained deep neural network (DNN) model which instantly estimates the …

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The Impact Of Inkjet Parameters And Environmental Conditions In Binder Jetting Additive Manufacturing, Trenton Miles Colton Dec 2021

The Impact Of Inkjet Parameters And Environmental Conditions In Binder Jetting Additive Manufacturing, Trenton Miles Colton

Theses and Dissertations

Binder jetting is an additive manufacturing process in which a part is fabricated layer-by-layer using inkjet technology to selectively dispense binder into powder layers in a designated area. The approach gives this process significant advantages over other additive manufacturing processes such as lower cost, capability to print in a wide range of materials, and little to no heat applied. Although binder jetting has many advantages and has been successful implemented in various industries its overall rate of adoption is slow compared to other processes. This is largely due to poor mechanical properties and consistency in printing which stems from a …

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A Data-Driven Approach For The Investigation Of Microstructural Effects On The Effective Piezoelectric Responses Of Additively Manufactured Triply Periodic Bi-Continuous Piezocomposite, Wenhua Yang Dec 2021

A Data-Driven Approach For The Investigation Of Microstructural Effects On The Effective Piezoelectric Responses Of Additively Manufactured Triply Periodic Bi-Continuous Piezocomposite, Wenhua Yang

Theses and Dissertations

A two-scale model consisting of ceramic grain scale and composite scale are developed to systematically evaluate the effects of microstructures (e.g., residual pores, grain size, texture) and geometry on the piezoelectric responses of the polarized triply periodic bi-continuous (TPC) piezocomposites. These TPC piezocomposites were fabricated by a recently developed additive manufacturing (AM) process named suspension-enclosing projection-stereolithography (SEPS) under different process conditions. In the model, the Fourier spectral iterative perturbation method (FSIPM) and the finite element method will be adopted for the calculation at the grain and composite scale, respectively. On the grain scale, a DL approach based on stacked generative …

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Characterization And Enhancement Of Fatigue And Fracture Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Manjarik Mrinal Dec 2021

Characterization And Enhancement Of Fatigue And Fracture Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Manjarik Mrinal

Mechanical and Aerospace Engineering Dissertations - Archive

Fused filament fabrication (FFF) show high anisotropy and reduced mechanical properties as compared to conventional manufacturing techniques. This happens due to the poor interlaminar bonding between the layers, as a result of premature halt of bond healing process. Previous research works show multiple approaches to improve the bond quality to enhance the mechanical properties of FFF parts, however these are complex and expensive techniques. In this work a novel print head assembly is presented to offer a simple and effective solution by applying a thermal field to the part as it is being printed to preheat the previously deposited layer, …

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A Machine Learning Method For The Prediction Of Melt Pool Geometries Created By Laser Powder Bed Fusion, Jonathan Ciaccio Dec 2021

A Machine Learning Method For The Prediction Of Melt Pool Geometries Created By Laser Powder Bed Fusion, Jonathan Ciaccio

LSU New Orleans Theses and Dissertations

A machine learning model is created to predict melt pool geometries of Ti-6Al-4V alloy created by the laser powder bed fusion process. Data is collected through an extensive literature survey, using results from both experiments and CFD modeling. The model focuses on five key input parameters that influence melt pool geometries: laser power, scanning speed, spot size, powder density, and powder layer thickness. The two outputs of the model are melt pool width and melt pool depth. The model is trained and tested by using the k fold cross validation technique. Multiple regression models are then applied to find the …

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Additive Manufacturing Using Robotic Manipulators, Fdm, And Aerosol Jet Printers., Alexander Curry Dec 2021

Additive Manufacturing Using Robotic Manipulators, Fdm, And Aerosol Jet Printers., Alexander Curry

Electronic Theses and Dissertations

Additive manufacturing has created countless new opportunities for fabrication of devices in the past few years. Advances in additive manufacturing continue to change the way that many devices are fabricated by simplifying processes and often lowering cost. Fused deposition modeling (FDM) is the most common form of 3D printing. It is a well-developed process that can print various plastic materials into three-dimensional structures. This technology is used in a lot of industries for rapid prototyping and sometimes small batch manufacturing. It is very inexpensive, and a prototype can be created in a few hours, rather than days. This is useful …

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Selective Laser Melting Of Titanium Diboride: A Study Of The Energy Density Effects, Lazaro Lopez Mendez Dec 2021

Selective Laser Melting Of Titanium Diboride: A Study Of The Energy Density Effects, Lazaro Lopez Mendez

Theses and Dissertations

Natural titanium diboride (TiB2) has been reported the 5th hardest material on earth. Due to its superior properties, such as high density, high elastic modulus, and high compressive strength, TiB2 becomes one of the most suitable ceramic reinforcements for applications with severe friction and heavy loading conditions. This study is intended to produce TiB2 using 3D additive manufacture (AM) technology, and then to understand the tribological property of the AM fabricated TiB2 specimens. In this study, a laser additive alloying (LAA) process was developed based on a Renishaw AM laser system. One mm thick samples were prepared using the LAA …

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Optimized Tip Cooling Using Am Process, Alberto H. Gamez, Lourdes Sarmiento Martinez, Andrew Van Bogelen Dec 2021

Optimized Tip Cooling Using Am Process, Alberto H. Gamez, Lourdes Sarmiento Martinez, Andrew Van Bogelen

Mechanical Engineering

This Final Design Review (FDR) reports on the senior design project undertaken by our team of mechanical engineering seniors at California Polytechnic State University, San Luis Obispo. This project seeks to use the additive manufacturing process to improve the existing design of a Taurus 60 gas turbine injector tip. The current injector tip is owned by Solar Turbines, a designer and manufacturer of gas turbines for electric generation, propulsion, as well as natural resource transportation. The challenge at hand is to design a new injector tip that will be reliable for at least 60,000 hours and provide ease of replacement, …

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Post-Processing And Characterization Of Additive Manufactured Carbon Fiber Reinforced Semi-Crystalline Polymers, Patricia Revolinsky Dec 2021

Post-Processing And Characterization Of Additive Manufactured Carbon Fiber Reinforced Semi-Crystalline Polymers, Patricia Revolinsky

Mechanical & Aerospace Engineering Theses & Dissertations

The aim of this work is to study the effect of post-processing on additive manufactured (AM) continuous carbon fiber reinforced plastics (CFRPs) performance. As-printed AM CFRPs do not perform as well as conventionally manufactured CFRPs with the same composition. Possible improvements to AM CFRP performance include annealing and applying uniaxial pressure with elevated temperature. Samples were subjected to pressure and temperature treatments and annealing at a constant temperature. Treated materials were subjected to three-point bending tests, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) to characterize and assess sample performance. Results were assessed for flexural strength, …

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Fatigue Damage Quantification And Life Estimation With Provision For Microstructure, Arash Pourbagheri Jirandehi Nov 2021

Fatigue Damage Quantification And Life Estimation With Provision For Microstructure, Arash Pourbagheri Jirandehi

LSU Doctoral Dissertations

This dissertation provides methodologies for the quantification of different forms of fatigue damage by considering the role of microstructure. The laws of thermodynamics in conjunction with Finite Element Method (FEM) are utilized to devise thermodynamically-base frameworks for the estimation of cyclic damage in polycrystalline metals. Accordingly, a microstructure-sensitive platform for fatigue life estimation is introduced. The proposed framework is assessed for 3D printed metallic alloys at room and elevated temperatures. Further, it is used to analyze the fatigue performance difference between additively manufactured Inconel 718 in three print orientations. This research is of fundamental vital interest because it ensures that …

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Experimental Investigation Of Additive Manufacturing Of Continuous Carbon Fiber Composites With Multifunctional Electro-Tensile Properties, Ritesh Ghimire, Frank W. Liou Nov 2021

Experimental Investigation Of Additive Manufacturing Of Continuous Carbon Fiber Composites With Multifunctional Electro-Tensile Properties, Ritesh Ghimire, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Manufacturing processes for monofunctional and multifunctional materials vary depending on the design optimization. Multifunctional continuous carbon fiber composites provide great potential in achieving coupled structural and electrical properties for their applications in aircraft, unmanned aircraft systems, and spacecraft. Proper optimization of tensile and electrical properties offers benefits early in the design and continuous operational safety phases to obtain coupled multifunctional properties. In this paper, fused filament fabrication additive manufacturing (AM) technique was used to fabricate continuous carbon fiber solid laminated composites test coupons. The proposed new method characterizes the electrical conductivity's coupled effects on the tensile properties, including the failure …

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Additive Manufacturing Of Miniaturized Peak Temperature Monitors For In-Pile Applications, Kiyo T. Fujimoto, Yaqiao Wu, David Estrada Nov 2021

Additive Manufacturing Of Miniaturized Peak Temperature Monitors For In-Pile Applications, Kiyo T. Fujimoto, Yaqiao Wu, David Estrada

Materials Science and Engineering Faculty Publications and Presentations

Passive monitoring techniques have been used for peak temperature measurements during irradiation tests by exploiting the melting point of well-characterized materials. Recent efforts to expand the capabilities of such peak temperature detection instrumentation include the development and testing of additively manufactured (AM) melt wires. In an effort to demonstrate and benchmark the performance and reliability of AM melt wires, we conducted a study to compare prototypical standard melt wires to an AM melt wire capsule, composed of printed aluminum, zinc, and tin melt wires. The lowest melting-point material used was Sn, with a melting point of approximately 230 °C, Zn …

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Additive Manufacturing Of Stainless Steel -- Copper Functionally Graded Materials Via Inconel 718 Interlayer, Xinchang Zhang, Lan Li, Frank W. Liou Nov 2021

Additive Manufacturing Of Stainless Steel -- Copper Functionally Graded Materials Via Inconel 718 Interlayer, Xinchang Zhang, Lan Li, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The joining of dissimilar materials is becoming increasingly prevalent to integrate different material properties to enhance design flexibility and overall performance. This study introduced an innovative approach to additively manufacture copper on 316L stainless steel (SS316L) via Inconel 718 interlayers using directed energy deposition (DED). The novel multi-material structure was studied both experimentally and theoretically. The microstructure, tensile properties, microhardness, and thermal performance of the structure were characterized. Residual stress distribution over the structure was revealed by experimental-validated numerical modeling. The result exhibits that defect-free structures with excellent interfacial bonding can be achieved by introducing Inconel 718 interlayers. The bonding …

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A Novel Laser-Aided Machining And Polishing Process For Additive Manufacturing Materials With Multiple Endmill Emulating Scan Patterns, Mohammad Masud Parvez, Sahil Patel, Sriram Praneeth Isanaka, Frank W. Liou Oct 2021

A Novel Laser-Aided Machining And Polishing Process For Additive Manufacturing Materials With Multiple Endmill Emulating Scan Patterns, Mohammad Masud Parvez, Sahil Patel, Sriram Praneeth Isanaka, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In additive manufacturing (AM), the surface roughness of the deposited parts remains significantly higher than the admissible range for most applications. Additionally, the surface topography of AM parts exhibits waviness profiles between tracks and layers. Therefore, post-processing is indispensable to improve surface quality. Laser-aided machining and polishing can be effective surface improvement processes that can be used due to their availability as the primary energy sources in many metal AM processes. While the initial roughness and waviness of the surface of most AM parts are very high, to achieve dimensional accuracy and minimize roughness, a high input energy density is …

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Micromechanics Of Additively Manufactured Materials Under Dynamic Loading, Christopher Rueben Johnson Oct 2021

Micromechanics Of Additively Manufactured Materials Under Dynamic Loading, Christopher Rueben Johnson

Dissertations (1934 -)

Ongoing works aim to develop a predictive computational framework whichcan be utilized to shorten the design and certification cycle of additively manufactured (AM) 304L stainless steel (SS304L). High fidelity experiments are utilized to validate and parameterize the computational framework. Results have detailed differing mechanical responses across a breadth of strain rates for wrought and AM SS304L. Differences are attributed to the microstructural properties resulting from the fabrication and treatment of the materials. This work aims to supplement preexisting high strain rate compressive strength experimental data sets to further quantify process-structure-property (PSP) relationships in development of the computational framework. Materials investigated …

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3d Printed Concrete & Polymer Concrete For Infrastructure Applications, Daniel Heras Murcia Sep 2021

3d Printed Concrete & Polymer Concrete For Infrastructure Applications, Daniel Heras Murcia

Civil Engineering ETDs

Additive manufacturing technology has been established as one of the fastest-growing building technologies worldwide. Three-dimensional concrete printing (3DCP) has developed an increasing interest in the last decade due to its prospects as a transformative technology for industries such as the concrete precast. Besides the improvements in automation technologies in construction, traditional construction has faced considerable challenges: high accident rates, labor dependency, significant potential for automation, and high costs associated with the use of traditional formwork. In this context, three-dimensional concrete, also referred to as physical prototyping, is a novel construction technique in which the concrete is extruded layer-to-layer. 3DCP is …

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Evaluation Of Additively Manufactured Lattices Under High Strain Rate Impact, Derek G. Spear Sep 2021

Evaluation Of Additively Manufactured Lattices Under High Strain Rate Impact, Derek G. Spear

Theses and Dissertations

Several additively manufactured lattice designs and configurations were evaluated under compression loads under various strain rates from quasi-static to highly dynamic. These experiments examined how the mechanical behavior of the lattice changed based on the lattice design properties and the applied strain rates. The modulus of elasticity, yield strength, plateau stress, and toughness were observed to decrease with an increase in strain rate, revealing that the lattice designs exhibit a negative strain rate sensitivity. A new lattice flow stress model was developed to account for the mechanical response of the lattice and was incorporated into a computational model for simulation. …

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Laser-Defined Graphene Strain Sensor Directly Fabricated On 3d-Printed Structure, Tyler M. Webb, Twinkle Pandhi, David Estrada Sep 2021

Laser-Defined Graphene Strain Sensor Directly Fabricated On 3d-Printed Structure, Tyler M. Webb, Twinkle Pandhi, David Estrada

Materials Science and Engineering Faculty Publications and Presentations

A direct-write method to fabricate a strain sensor directly on a structure of interest is reported. In this method, a commercial graphene ink is printed as a square patch (6 mm square) on the structure. The patch is dried at 100 °C for 30 min to remove residual solvents but the printed graphene remains in an insulative state. By scanning a focused laser (830 nm, 100 mW), the graphene becomes electrically conductive and exhibits a piezoresistive effect and a low temperature coefficient of resistance of −0.0006 °C−1. Using this approach, the laser defines a strain sensor pattern on …

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Active Thermography For Additive Manufacturing Processes, Nicholas Jay Wallace Aug 2021

Active Thermography For Additive Manufacturing Processes, Nicholas Jay Wallace

Theses and Dissertations

The goal of the research conducted for this master's thesis is to understand if active thermography is a suitable technique to detect (identify) and measure (approximate depth and or size) defects in additive manufacturing (AM) processes. Although other non-destructive measurement techniques exist, active thermography is an attractive option for AM applications because of the short measurement times that could be implemented between each layer of a print, and because of the relatively inexpensive equipment required. However, pulse thermography is typically applied to detect larger defects (>1 mm) in materials with high thermal conductivity. It was uncertain if active thermography …

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Feasibility And Impact Of Liquid/Liquid-Encased Dopants As Method Of Composition Control In Laser Powder Bed Fusion, Taylor Matthew Davis Aug 2021

Feasibility And Impact Of Liquid/Liquid-Encased Dopants As Method Of Composition Control In Laser Powder Bed Fusion, Taylor Matthew Davis

Theses and Dissertations

Additive manufacturing (AM) – and laser powder bed fusion (LPBF) specifically – constructs geometry that would not be possible using standard manufacturing techniques. This geometric versatility allows integration of multiple components into a single part. While this practice can reduce weight and part count, there are also serious drawbacks. One is that the LPBF process can only build parts with a single material. This limitation generally results in over-designing some areas of the part to compensate for the compromise in material choice. Over-designing can lead to decreased functional efficiency, increased weight, etc. in LPBF parts. Methods to control the material …

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Characterization And Enhancement Of Mechanical Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Rhugdhrivya Rane Aug 2021

Characterization And Enhancement Of Mechanical Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Rhugdhrivya Rane

Mechanical and Aerospace Engineering Dissertations - Archive

Fused filament fabrication is one of the most common and widely used additive manufacturing techniques. Owing to its ease of use, availability and cheap feedstock it provides a significant advantage over other AM techniques. But these advantages are overshadowed by the fact that FFF parts show high anisotropy and reduced mechanical properties as compared to conventional manufacturing techniques. Literature review of previous research works show multiple approaches to enhance the mechanical properties of FFF parts but each of these techniques have limitations to either the geometries that can be printed or involve complex expensive setups. In one such technique a …

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Investigation Of Different Hatch Strategies On High Entropy Alloy Fabrication By Selective Laser Melting, Joni Chandra Dhar Aug 2021

Investigation Of Different Hatch Strategies On High Entropy Alloy Fabrication By Selective Laser Melting, Joni Chandra Dhar

Theses and Dissertations

This study investigated the synthesis of CuCrFeNiTiAl high entropy alloy (HEA) from pure elements using selective laser melting (SLM). The objectives are to validate the feasibility of the HEA fabrication from elemental powder materials, and to examine the effect of various hatch strategies and energy densities on the microstructures and other materials properties. 3D samples of CuCrFeNiTiAl alloy were fabricated under different energy densities and with different scan vector lengths. The as-built samples were characterized by X-ray diffraction (XRD), and the microstructures were observed using scanning electron microscopy (SEM). The XRD results showed that face centered cubic, and body centered …

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Phase Change Temperature Sensor For High Radiation Environment: Material, Additive Technology And Structure Development, Al Amin Ahmed Simon Aug 2021

Phase Change Temperature Sensor For High Radiation Environment: Material, Additive Technology And Structure Development, Al Amin Ahmed Simon

Boise State University Theses and Dissertations

Performance of any sensor in a nuclear reactor involves reliable operation under a harsh environment (i.e., high temperature, neutron irradiation, and a high dose of ionizing radiation). In this environment, accurate and continuous monitoring of temperature is critical for the reactor's stability and proper functionality. Furthermore, during the development and testing stages of new materials and structural components for these systems, it is imperative to collect in-situ measurement data about the exact test conditions for real-time analysis of their performance. To meet the compelling need of such sensing devices, we propose radiation-hard temperature sensors based on the phase change phenomenon …

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