Metallurgy Commons^™

Electrical Properties Of A Novel Solid Biopolymer Electrolyte Based On Algi-Nate Incorporated With Citric Acid, Ahmad Faizrin Ahmad Fuzlin, Noor Syahida Ismail, Yuki Nagao, Ahmad Salihin Samsudin

Makara Journal of Technology

In the present study, a novel solid biopolymer electrolyte (SBE) system is introduced by doping citric acid into alginate polymer. A sample of the alginate-citric acid SBE system was prepared via a solution casting technique. Using electrical impedance spectroscopy (EIS), the electrolytes of alginate-citric acid analyzed from 5 Hz to 1 MHz achieved the highest conductivity at 20 wt.% of 5.49 × 10-7 S cm-1. The temperature dependence of various citric acid amounts obeyed the Arrhenius rule with R2~1, where all SBE systems were thermally activated with increasing temperature. The dielectric studies of the alginate-citric acid SBE system showed non-Debye …

Wavelet Transform On Digital Rainbow Hologram Based On Spectral Compression For Quality Enhancement In 3d Display Media, Ucuk Darusalam, Panca Dewi Pamungkasari

Makara Journal of Technology

A digital rainbow hologram (DRH) is a potential next-generation three-dimensional display media for the development of modern and smart electronics devices. It is one of the methods that can support the characteristic whereby a realistic display media occupies the space that the real object would have occupied. Since a rainbow hologram records a large amount of spatial or temporal frequency component from the object that represents the rainbow spectrum, a large amount of information needs to be decoded digitally. In this paper, to reconstruct a DRH, we propose a novel method based on the modulation of red, green, and blue …

Data Fusion Method Based On Adaptive Kalman Filtering, Bernadus Herdi Sirenden

Makara Journal of Technology

This paper discusses data fusion methods to combine the data from a rotary encoder and ultrasonic sensor. Both sensors are used in a micro-flow calibration system developed by the Research Center of Metrology LIPI. The methods studied are hierarchical data fusion and Kalman filtering. Three types of Kalman filters (KFs) are compared: the conventional Kalman filter and two adaptive Kalman filters. Moreover, a method to combine the uncertainty results from KF in hierarchical data fusion is proposed. The aim of this study is to find appropriate methods of data fusion that can be implemented in micro-flow calibration systems. Data from …

Sorption-Based Energy Storage Systems: A Review, Kyaw Thu, Nasruddin Nasruddin, Sourav Mitra, Bidyut Baran Saha

Makara Journal of Technology

Mismatched timing between the supply and demand of energy calls for reliable storage systems. Energy storage systems have become further significant with the widespread implementation of renewable energy. These systems can mitigate problems that are often associated with renewable energy sources such as supply unreliability while meeting the de-mand during peak hours. Energy can be stored in various forms, yet storage systems can be generally grouped based on their output forms, namely (i) electricity and (ii) heat or thermal energy. Electrical energy is the most convenient and effective form since it can power almost all modern devices. However, the electricity …

Process Parameter Development Of Additively Manufactured Af9628 Weapons Steel, Erin M. Hager

Theses and Dissertations

The manufacture of components in Additive Manufacturing processes is limited by the range of materials available. Qualification of materials for Additive Manufacturing is time intensive, and is often specific to a single type of machine. In this study, an approach to selecting power, speed, and hatch spacing values for a newly powderized material, AF9628 weapons steel, is described that results in highly dense (>99.9%) parts on an MLab 200R Cusing. Initial power and speed values used in a weld track study were selected based on a survey of parameters used on similar materials, with a focus on the energy …

Removal Of Synthetic Azo Dye Using Bimetallic Nickel-Iron Nanoparticles, Shelby L. Foster, Katie Estoque, Michael Voecks, Nikki Rentz, Lauren F. Greenlee

Chemical Engineering Faculty Publications and Presentations

Bimetallic nanoparticles comprised of iron (Fe) and nickel (Ni) were investigated for the removal of an azo dye contaminant in water. Morphology (core shell and alloy) and metal molar ratio (Ni2Fe10, Ni5Fe10, and Ni10Fe10) were tested as key nanoparticle properties. The shelf life of the nanoparticles was tested over a 3-week period, and the effect of initial nanoparticle concentration on dye removal was evaluated. The highest initial nanoparticle concentration (1000 mg/L) showed consistent Orange G removal and the greatest extent of dye removal, as compared to the other tested concentrations (i.e., 750 mg/L, 500 mg/L, and 250 mg/L) for the …

On The Feasibility Of Tailoring Copper-Nickel Functionally Graded Materials Fabricated Through Laser Metal Deposition, Sreekar Karnati, Yunlu Zhang, Frank W. Liou, Joseph William Newkirk

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this study, pulse‐width modulation of laser power was identified as a feasible means for varying the chemical gradient in copper—nickel‐graded materials. Graded material deposits of 70 wt. %. copper‐30 wt. %. nickel on 100 wt. %. nickel and vice versa were deposited and characterized. The 70/30 copper—nickel weight ratio in the feedstock powder was achieved through blending elemental copper and 96 wt. %. Ni—Delero‐22 alloy. At the dissimilar material interface over the course of four layers, the duty cycle of power was ramped down from a high value to optimized deposition conditions. This change was theorized to influence the …

Leaching Characteristics Of Rare Earth Elements From Bituminous Coal-Based Sources, Xinbo Yang

Theses and Dissertations--Mining Engineering

The demand for rare earth elements (REEs) has increased over the last decade due to applications in high technology devices including those in the defense industry. The recovery of REEs from primary sources such as rare earth minerals are viable using physical separations followed by chemical processing. However, weak market values and environmental concerns have limited the viability of such operations. On the other hand, REE recovery from secondary sources such as apatite ore, bauxite waste, and waste recycling, provides an opportunity to take advantage of a resource that does not require mining costs as well as other associated costs …

Performance Of Plunge Depth Control Methods During Friction Stir Welding, Jinyoung Yoon, Cheolhee Kim, Sehun Rhee

Mechanical and Materials Engineering Faculty Publications and Presentations

Friction stir welding is a preferred solid state welding process for Al/Fe joints, and in friction stir lap welding, the plunge depth is the most critical parameter for joint strength. We compared three plunge depth control methods, namely conventional position control, offset position control, and deflection compensation control in the friction stir lap welding of 3 mm-thick Al 5083-O alloy over 1.2 mm-thick DP 590 steel. The desired plunge depth was 0.2 mm into the steel sheet. However, the pin did not reach the steel surface under conventional position control due to deflection of the vertical axis of the welding …

Development Of Stage-I Tempered High Strength Cast Steel For Ground Engaging Tools, Viraj Ashok Athavale

Doctoral Dissertations

"Ground Engaging Tools (GET) are the expendable replacement parts used in heavy machinery used with mining or construction equipment. GET’s protect the expensive machine components from the wear and tear found common in high-impact or high-abrasion environments. The goal of this project is to develop advanced next-generation alloy choices that outperforms the existing GET materials. A method of predicting tempered hardness of mixed microstructures was formulated. Using this model, two alloy series viz. Cr-Ni-Mo and Mn-Si-Mo-V were proposed and experimented with the goal of obtaining a high strength and impact resistant cast steel. Cast iterations of Cr-Ni-Mo alloy series were …

สัมประสิทธิ์การแพร่ของไฮโดรเจนผ่านผิวเคลือบทองคำ และผิวเคลือบนิกเกิลบนเหล็กกล้าไร้สนิม Aisi 304, กฤตยชญ์ วรรณโพธิ์กลาง

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้เกิดจากพื้นฐานความคิดว่าชั้นเคลือบโลหะบนเหล็กกล้าไร้สนิม AISI 304 เป็นชั้นต้านทานการแพร่ของไฮโดรเจนเพื่อชะลอการแตกร้าวจากการช่วยของไฮโดรเจน (Hydrogen Assisted Cracking, HAC) ในงานวิจัยใช้ขั้นตอนการดำเนินงานตามมาตรฐาน ASTM G148-97 ตรวจวัดสัมประสิทธิ์การแพร่ไฮโดรเจนประสิทธิผล ชั้นเคลือบนิกเกิลและทองคำด้วยไฟฟ้าบนชิ้นงานเหล็กกล้าไร้สนิม AISI 304 แผ่นบางตามขั้นตอนในอุตสาหกรรมซึ่งเป็นด้านเซลล์อัดประจุถูกตรวจสอบเฟสโดยใช้การเลี้ยวเบนของรังสีเอ็กซ์ และวัดขนาดความหนาเฉลี่ยด้วยภาพถ่ายอิเล็กตรอนแบบส่องกราด ด้านเซลล์ออกซิไดซ์ถูกเคลือบด้วยชั้นเคลือบนิกเกิล ผลการทดลองพบว่าที่อุณหภูมิ 301 K จากการคำนวณใช้เวลาการซึมผ่านและเวลาล่าช้า ค่าสัมประสิทธิ์การแพร่ไฮโดรเจนประสิทธิผลเฉลี่ยของเหล็กกล้าไร้สนิม AISI 304 ที่ไม่มีชั้นเคลือบด้านการอัดประจุ เหล็กกล้าไร้สนิม AISI 304 ที่มีชั้นเคลือบนิกเกิลด้วยไฟฟ้าด้านการอัดประจุ และเหล็กกล้าไร้สนิม AISI 304 ที่มีชั้นเคลือบทองคำด้วยไฟฟ้าด้านการอัดประจุ เท่ากับ 5.98x10-13, 6.05x10-13 และ 3.57x10-14 m2ꞏs-1 ตามลำดับ จากการคำนวณสัมประสิทธิ์การแพร่ไฮโดรเจนประสิทธิผลในเหล็กกล้าไร้สนิม AISI 304 ในชั้นเคลือบนิกเกิลและในชั้นเคลือบทองคำ มีค่าเท่ากับ 7.99x10-13, 3.40x10-14 และ 5.19x10-16 m2ꞏs-1 ตามลำดับ จากผลข้างต้น กล่าวได้ว่า ชั้นเคลือบทองคำด้วยไฟฟ้ามีประสิทธิภาพการต้านทานการแพร่ของไฮโดรเจนดีที่สุดเมื่อเปรียบเทียบกับเหล็กกล้าไร้สนิม AISI 304 และชั้นเคลือบนิกเกิลด้วยไฟฟ้า

Effects Of Electrodeposition Parameters On Zn-Tio2 Coating For Zinc-Ion Battery, Kittima Lolupiman

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research work has an aim to modify and develop to obtain environmentally friendly Zinc ion battery (ZIB) with low cost. Usually, the limit of Zn ion battery is occurred by dendrite growth during cycling of Zn anode leading to shorter service lifetime. Therefore, in this present work had an idea to modify electrodeposition process by adding TiO2 nano particles into coated Zn layers. This composite deposits were used as the anode materials of ZIBs. The only Zn and Zn/TiO2 composite coatings were deposited on the stainless-steel foil as modified anodes. The plating and stripping tests of symmetric cells reveal …

Oxide Inclusion Evolution And Factors That Influence Their Size And Morphology, Obinna M. Adaba

Doctoral Dissertations

"The evolution of oxide inclusion size distribution and the shape of the distribution during steelmaking and casting and the process variables that influence the inclusion characteristics at different stages were investigated and documented. A statistical method for transforming the 2D size distribution to their actual 3D distributions and the application of a kinetic model to determine nucleation and growth mechanisms were tested. Finally, laboratory experiments were performed to study the effects of preexisting inclusions, steel active oxygen content, and supersaturation on the size and morphology of Al₂O₃ inclusions.

The inclusion size, composition, and morphology following steel deoxidation …

Enhanced Surface Integrity With Thermally Stable Residual Stress Fields And Nanostructures In Cryogenic Processing Of Titanium Alloy Ti-6al-4v, James R. Caudill

Theses and Dissertations--Mechanical and Aerospace Engineering

Burnishing is a chipless finishing process used to improve surface integrity by severe plastic deformation (SPD) of surface asperities. As surface integrity in large measure defines the functional performance and fatigue life of aerospace alloys, burnishing is thus a means of increasing the fatigue life of critical components, such as turbine and compressor blades in gas turbine engines. Therefore, the primary objective of this dissertation is to characterize the burnishing-induced surface integrity of Ti-6Al-4V alloy in terms of the implemented processing parameters. As the impact of cooling mechanisms on surface integrity from SPD processing is largely unexplored, a particular emphasis …

Effect Of Development Of Scandium Trialuminide Precipitates On Corrosion And Mechanical Behavior In Aluminum-Magnesium Alloys, Carson Williams

Dissertations, Master's Theses and Master's Reports

Development of aluminum alloys has seen an increase in attention in recent years. The 5xxx series of Al-Mg alloys has the potential to provide strong, lightweight materials in various industry applications, however issues with strain formability and corrosion hinder the development of these alloys. The addition of Sc for developing Al₃Sc precipitates provides considerable precipitation strengthening as well as grain refinement characteristics that can help mitigate these issues. Alloys with varied Mg content were analyzed for heat treatment aging responses and precipitate formation, changes in mechanical behavior related to the Portevin-le Chatelier effect, and effects on intergranular corrosion …

Investigating Microalloying Elements To Accelerate Zirconium Trialuminide Precipitation In Aluminum Alloys, Philip D. Staublin

Dissertations, Master's Theses and Master's Reports

Precipitation of the L1₂-structured coherent Al₃Zr trialuminide phase in aluminum-zirconium alloys increases the alloy strength. Precipitation of a more refined dispersion of Al₃Zr can further increase the strength of these alloys. The addition of microalloying elements which bind to zirconium may accelerate the precipitation kinetics, allowing for nucleation of a greater number of precipitates and faster precipitate growth. Zirconium binding energies are computed for a wide range of elements, based on which the elements tin, antimony, and tellurium were selected for investigation. Ternary Al-Zr-X alloys (X = Sn, Sb, Te) were cast and heat …

Integrated Computational Materials Engineering (Icme) Investigation Of Electrical Conductivity And Thermodynamic Stability For Precipitation Strengthened Al-Zn-Zr And Al-Zn-Ni Ternary Alloys, Oladeji Fadayomi

Dissertations, Master's Theses and Master's Reports

High electrical conductivity Al-Zn-TM (TM=Transition metals) alloys with improved mechanical properties and thermal resistance are developed with an integrated computational material engineering (ICME) strategy. From a series of ab initio density functional theory (DFT) simulations assessing combinations of ternary alloys, Al-Zn-Ni and Al-Zn-Zr are determined as alloys with relatively high electrical conductivity compared to several other ternary Al alloy combinations. The zero-temperature stable structure of precipitates formed in these alloys are determined from computed enthalpy of formation as L1₂, with particular focus of examining the influence of Zn on stabilizing the desired L1₂ precipitate phase.

Scanning transmission …

Recovery Of Rare Earth Elements (Rees) From Coal Mine Drainage Sludge Leachate, Panpan Ren

Graduate Theses, Dissertations, and Problem Reports (ETD)

Acid mine drainage (AMD) is the primary cause of aquatic habitat loss in the Appalachian Coal Basin and many other mining districts across the U.S. and the world. The objective of this work is to develop a cost-effective and environmentally benign process to treat and recover Rare Earth Elements (REEs) from AMD. Solvent extraction (SX) is one effective way to turn AMD into a commercially viable feedstock for rare earth production.

In this work, SX experiments were conducted on Y-Ca-Mg-Al-HDEHP-n-heptane-HNO3-H2O system to simulate AMD treatment for Yttrium recovery by changing four parameters: pH values, concentration ratio of Yttrium (Y) over …

Metallic Systems At The Nano And Micro Scale: Bimetallic Nanoparticles As Catalysts And Mcraly Bond Coats In Thermal Barrier Coatings, Kenneth Kane

Theses and Dissertations

The dissertation is split into two parts. The first part will be focused on changes in material properties found at the nanoscale, as miscibility and electronic structure can change significantly with size. The formation of classically-immiscible bimetallic nanoparticles (BNPs) becomes favorable at the nanoscale and novel catalytic properties can emerge from the bimetallic alloying. The formation of alloyed and non-alloyed BNPs is achieved through pulse laser ablation (PLA) and a significant increase in catalytic activity is observed for both. Recently discovered, the increased activity in the non-alloyed BNPs, deemed multicomponent photocatalysis, is examined and the proposed mechanism discussed. The second …

Development Of Castrip Dual Phase Steel, Brenton Allen Hrebec

Masters Theses

“Thermomechanical processing necessary to produce DP 980 steel using CASTRIP hot band was investigated. The resultant steel has an ultimate tensile strength of 1038 MPa, yield strength of 744 MPa, and total elongation of 8.6%. These mechanical properties were achieved by batch annealing the hot band at 649°C for 48 hours and cold rolling to a 20% reduction. The steel was continuously annealed to simulate a galvanization cycle with an intercritical temperature of 810°C. The possibility of improving the texture of the steel by warm rolling under dynamic strain aging conditions was investigated. Dynamic strain aging in the CASTRIP hot …