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Full-Text Articles in Engineering Science and Materials
Characterization Of Aerosol Jet Printed Silver Thin Films Sintered By A Scanning Laser, William A. Metzger
Characterization Of Aerosol Jet Printed Silver Thin Films Sintered By A Scanning Laser, William A. Metzger
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Direct write printing, which is part of additive manufacturing (AM) technology, offers unique capabilities that can complement traditional methods of electronics fabrication. Printing of electrical interconnects via aerosolization is one of the areas in AM that is very important in electronics fabrication. Post-print sintering is a critical step in printed electrical interconnects because it strongly influences the electrical resistivity of the interconnects. Interconnects require the lowest possible resistivity to achieve better performance. Thermal sintering is the most common technique employed in printed interconnects. However, it is limited to substrates that can handle the high temperature requirement for sintering. For polymers …
Processing And Characterization Of Inkjet Printed Batio3/Su-8 Nanocomposite Dielectrics, Mustapha A. Muhammad
Processing And Characterization Of Inkjet Printed Batio3/Su-8 Nanocomposite Dielectrics, Mustapha A. Muhammad
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The persistent demand for flexible and wearable electronic components in healthcare, aerospace, media, and transit applications has led to a significant shift from traditional electronics processes to printed electronics. Printed electronics are anticipated to establish itself as the industry's dominant force due to their enhanced flexibility, rapid prototyping capabilities, and seamless integration with everyday objects. They are cost-effective and have the scalable option for large-scale production because additive manufacturing techniques are used. Among the various printing methods available, inkjet printing has recently gained popularity for printing electronics, especially capacitors that require precise and complex structures on different substrates. Inkjet printing …
Comparative Study Of Mof's In Phosphate Adsorption, Eniya Karunamurthy
Comparative Study Of Mof's In Phosphate Adsorption, Eniya Karunamurthy
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High concentrations of phosphate are known to adversely affect the environment. Excess phosphate can lead to eutrophication that eventually fosters uncontrollable growth of aquatic plants and algae. This can result in depletion of oxygen content which adversely impacts underwater organism’s survival rates. Metal organic frameworks (MOFs) consist of organic linkers in conjunction with metal ions or clusters arranged within a crystalline structure. They are highly porous and have larger surface area due to their ability to possess extensive void spaces while remaining bulky in nature. MOFs can absorb phosphate from aqueous solutions. We have investigated the use of commercially available …
Rheological Modeling And Inkjet Printability Of Electrode Ink Formulation For Miniature And Interdigital Lithium-Ion Batteries, Habib Temitope-Adebayo Ajose
Rheological Modeling And Inkjet Printability Of Electrode Ink Formulation For Miniature And Interdigital Lithium-Ion Batteries, Habib Temitope-Adebayo Ajose
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The rapid advancement of technology has resulted in a greater need for effective energy storage systems to meet the demands of the transportation and electronics industries. Among various energy storage systems, batteries are the most widely used, primarily because of their ability to store significant amounts of energy. In addition, lithium-ion batteries are prevalent for powering portable electronic devices due to their long cycle life, high energy density, and high operating voltage. The traditional doctor-blade approach has been used over the years for producing batteries. Currently, research is being directed to additively manufacture Li-ion batteries via Drop-on-Demand Inkjet Printing with …
Direct Ink Write Processing Of Signal Crossovers Using Aerosol Jet Printing Method, Lucas A. Clark
Direct Ink Write Processing Of Signal Crossovers Using Aerosol Jet Printing Method, Lucas A. Clark
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Electronics in different applications, such as in medical imaging devices, radar systems, communication transmitters, and optical drives, often require various power and signal lines to be integrated at board level. In such cases, different lines may cross over one another in three-dimensional space for efficient electronic integration. Crossovers are usually achieved by adding additional layers to a PCB. However, these additional layers increase the cost, weight, and complexity of the component. By creating a process and structure to offer board-level heterogenous integration, these factors may be reduced. RF-DC crossovers were designed and additively manufactured using an aerosol jet printer. Benzocyclobutene …
Effect Of Build Geometry And Build Parameters On Microstructure, Fatigue Life, And Tensile Properties Of Additively Manufactured Alloy 718, Anna Dunn
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Additive Manufacturing (AM), particularly laser powder bed fusion, is being studied for use in critical component applications. Tensile and fatigue testing shows differences when built using different laser powers. However, when fabricated in an as-printed geometry, the gauge sections of the two specimens are different and experience different thermal behavior. This work explores microhardness, microstructure size, Niobium segregation, and porosity from samples made with varying laser power and different build geometry sizes representative of the gauge sections in the tensile and fatigue bars. Results show that microhardness varies spatially across the sample. Smaller diameter metallographic coupons (fatigue diameter) have a …
Influence Of Fill Percentage And Baking Parameters On The Feedability Of Metal-Cored Arc Welding Wires, Angelica Marie Black
Influence Of Fill Percentage And Baking Parameters On The Feedability Of Metal-Cored Arc Welding Wires, Angelica Marie Black
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Adequate feedability is essential for GMAW processes to ensure efficiency. The feedability of a wire refers to the wire’s ability to feed continuously through the contact tip. While there are several known causes of feedability difficulties when using cored welding wires, there are many variables that have yet to be explored thoroughly. Three factors are investigated in this research to determine their effects on feedability of cored wires: fill percentage, baking time, and baking temperature. A set of metal-cored arc welding wires were created with various fill percentages, baking times, and baking temperatures. Tension testing, microhardness testing, microstructural characterization, and …
Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle
Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle
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Fused silica (silica glass) is transparent in the optical and near-infrared and has a low dielectric constant, making it suitable as a window material for radio frequency radiation. However, at high temperatures (>1100C), fused silica will easily creep and lose dimensional stability. Crystallized silica is much more creep resistant than fused silica. Silica crystallizes to many different structures including quartz, tridymite, and α- and β cristobalite. The only cubic polymorph, which is suitable for both optical and radio frequency transmission in polycrystalline form, is β -cristobalite. Unfortunately, this polymorph transforms to α-cristobalite at ~300C, and the volume change during …
Preparation And Characterization Of Porous Pdms For Printed Electronics, Eyad Khalid M. Balbaid
Preparation And Characterization Of Porous Pdms For Printed Electronics, Eyad Khalid M. Balbaid
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Fabricating an elastomeric substrate with internal features could provide a novel structure with distinctive mechanical properties that allow them to stretch, bend and absorb the impact force. To date, polydimethylsiloxane (PDMS) is a great candidate as a substrate for flexible electronic applications, due to easy fabrication, high stability and low cost. In the current thesis, porous PDMS samples are fabricated and characterized based on the particle size and the fusion of salt and sugar treated micro-regions. The liquid PDMS is prepared by mixing the silicon elastomer base (Sylgard 184) and elastomer curing agent using volume ration 10:1. The salt and …
Microstructural Characterization Of LensTm Ti-6al-4v: Investigating The Effects Of Process Variables Across Multiple Deposit Geometries, Laura Christine Davidson
Microstructural Characterization Of LensTm Ti-6al-4v: Investigating The Effects Of Process Variables Across Multiple Deposit Geometries, Laura Christine Davidson
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Laser based additive manufacturing of Ti-6Al-4V components is under consideration for aerospace applications. The mechanical properties of the finished components depend on their microstructure. Process mapping compares process variables such as heat source power, heat source travel speed, material feed rate, part preheat temperature and feature geometry to process outcomes such as microstructure, melt pool geometry and residual stresses. In this work, the microstructure of two-dimensional pads, multilayer pads, thin walls, and structural components at the steady state location was observed. A method for measuring β grain widths that allows for the calculation of standard deviations, confidence intervals, and variances …
Processing Of Ultra-Thin Film Of Un Modified C60 Fullerene Using The Langmuir-Blodgett Technique. Effect Of Structure On Stiffness And Optoelectric Properties, Hasanain Basim Altalebi
Processing Of Ultra-Thin Film Of Un Modified C60 Fullerene Using The Langmuir-Blodgett Technique. Effect Of Structure On Stiffness And Optoelectric Properties, Hasanain Basim Altalebi
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Monolayer films of C60 fullerene were for the first time produced successfully by using the Langmuir-Blodgett technique. The processing parameters were optimized and the structure of these films has been investigated using Scanning Tunneling Microscopy (STM) and Atomic Force Microscopy (AFM). Film stiffness was measured to be in the range of 15 MPa to 32 MPa depending on the nature of the solvent used to process the films. Optical transparency and electrical performance have been measured and correlated to the film structure. While 100% transparent, the film measured conductivity was in the range of 1013 S/m, that is orders of …