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Articles 1 - 30 of 62
Full-Text Articles in Metallurgy
Grain Size And Texture Effects On Deformation Behavior Of Az31 Magnesium Alloy, W. Yuan, R. S. Mishra
Grain Size And Texture Effects On Deformation Behavior Of Az31 Magnesium Alloy, W. Yuan, R. S. Mishra
Materials Science and Engineering Faculty Research & Creative Works
Cold rolled AZ31 magnesium alloy sheet was subjected to friction stir processing to generate four average grain sizes ranging from 0.8 to 9.6 μm. the processed material exhibited a strong basal fiber texture with the c-axis tilted about 35-55° towards the processing direction. the grain size and texture dependence of mechanical behavior were evaluated by using tensile testing along two orthogonal directions. Remarkably high ductility of ~65% was achieved in relatively coarse-grained material that fractured without developing necking when tested in the processing direction. the ductility decreased significantly to ~10% for ultrafine grained material as the tensile yield strength increased …
A Comparative Study On The Corrosion Resistance Of Cerium-Based Conversion Coatings On Az91d And Az31b Magnesium Alloys, C. E. Castano, Surender Maddela, Matthew J. O'Keefe, Y. M. Wang
A Comparative Study On The Corrosion Resistance Of Cerium-Based Conversion Coatings On Az91d And Az31b Magnesium Alloys, C. E. Castano, Surender Maddela, Matthew J. O'Keefe, Y. M. Wang
Materials Science and Engineering Faculty Research & Creative Works
In the present work a comparative study has been carried out on the surface morphology, electrochemical properties and corrosion performance of cerium-Based conversion coatings (CeCCs) on AZ91D and AZ31B magnesium alloys. the as-deposited coatings consisted of a two-layer structure: A continuous Mg/Al oxide transition layer of ∼ 50 nm thick and a CeCC layer of ∼ 400 nm thick. Potentiodynamic polarization and impedance spectroscopy results using a 0.6 wt.% NaCl and 0.6 wt.% (NH4)2SO4 electrolyte showed that cerium-Based conversion coatings enhanced the corrosion resistance of AZ91D and AZ31B magnesium alloys compared to polished uncoated samples. …
Fabrication Of Solid Solution Tungsten-Rhenium Alloys By High Energy Ball Milling And Spark Plasma Sintering, Cory C. Sparks
Fabrication Of Solid Solution Tungsten-Rhenium Alloys By High Energy Ball Milling And Spark Plasma Sintering, Cory C. Sparks
Boise State University Theses and Dissertations
Tungsten-rhenium powders of varying compositions were fabricated by spark plasma sintering (SPS). In initial exploration of the parameter space, W-25 at% Re powders were blended and consolidated by SPS at 1500 to 1900°C with sintering dwell times of 0 to 60 minutes. In addition, the influence of milling was investigated. W-25 at% Re powders were high-energy ball milled at 200 to 400 rpm for 5 hours and consolidated at 1700°C with sintering dwell times of 0 to 60 minutes. The sample densities, grain sizes, porosities, contamination level, and hardness values were measured. The intermetallic content, specifically the fraction of σ-phase, …
Physico-Chemical, And Sensory Properties Of Soy Based Gouda Cheese Analog Made From Different Concentration Of Fat, Sodium Citrate And Various Cheese Starter Cultures, Abu Amar, Ingrid Suryanti Surono
Physico-Chemical, And Sensory Properties Of Soy Based Gouda Cheese Analog Made From Different Concentration Of Fat, Sodium Citrate And Various Cheese Starter Cultures, Abu Amar, Ingrid Suryanti Surono
Makara Journal of Technology
Gouda cheese analog (GCA) was made using soy protein isolate (SPI), skim milk powder (SMP), fat (palm fat and butter fat), and water (W) at optimal ratio of SPI : SMP : F : W = 14 : 6 : 20 : 60. The effects of butter fat, sodium citrate, and cheese starter culture on the sensory properties of ripened product were assessed by preference test, hedonic test, and the texture profile analysis (TPA) of GCA. The free fatty acids, water-soluble nitrogen, and reduction in pH value of progel were also measured. The use of 100% butter fat (BF) produced …
Effects Of Deposition Parameters And Oxygen Addition On Properties Of Sputtered Indium Tin Oxide Films, Badrul Munir, Rachmat Adhi Wibowo, Kim Kyoo Ho
Effects Of Deposition Parameters And Oxygen Addition On Properties Of Sputtered Indium Tin Oxide Films, Badrul Munir, Rachmat Adhi Wibowo, Kim Kyoo Ho
Makara Journal of Technology
Indium tin oxide (ITO) films were sputtered on corning glass substrate. Oxygen admixture and sputtering deposition parameters were optimized to obtain the highest transparency as well as lowest resistivity. Structural, electrical and optical properties of the films were then examined. Increasing deposition rate and film thickness changed the crystallographic orientation from (222) to (400) and (440), as well as higher surface roughness. It was necessary to apply substrate heating during reposition to get films with better crystallinity. The lowest resistivity of 5.36 x 10-4 Ω•cm was obtained at 750 nm film thickness. The films’ resistivity was increased by addition of …
The Effect Of Rubber Mixing Process On The Curing Characteristics Of Natural Rubber, Abu Hasan, Rochmadi Rochmadi, Hary Sulistyo, Suharto Honggokusumo
The Effect Of Rubber Mixing Process On The Curing Characteristics Of Natural Rubber, Abu Hasan, Rochmadi Rochmadi, Hary Sulistyo, Suharto Honggokusumo
Makara Journal of Technology
This research is aimed at studying the relationship between rubber mixing processes and curing characteristics of natural rubber. The curing characteristic analysis was carried out through a natural rubber formula having been masticated and mixed, followed by curing. As many as four mastication methods were finely applied; each respected four sequences of rubber mixing process. In the first method, rubber was masticated for 5 minutes and then rubber chemicals and carbon black N 330 were simultaneously added. In the second and the third methods, rubber was masticated for 1 minute and then carbon blacks and rubber chemicals were also simultaneously …
Observation Of Center Disaster Damage On Pariaman And Wasior Using Differential Sar Interferometry (Dinsar), Dodi Sudiana, Mia Rizkinia
Observation Of Center Disaster Damage On Pariaman And Wasior Using Differential Sar Interferometry (Dinsar), Dodi Sudiana, Mia Rizkinia
Makara Journal of Technology
This study focuses on disaster observations in Pariaman (West Sumatera) and Wasior (Papua) using remote sensing techniques (differential SAR interferometry). Differential interferometry (DInSAR) method was performed on two PALSAR data sets with different acquisition months, i.e. about a month after and before disaster, respectively. The center damage of Pariaman earthquake and Wasior flood can be determined by deriving Land Subsidence using DInSAR method.
Coastal Physical Vulnerability Of Surabaya And Its Surrounding Area To Sea Level Rise, Sayidah Sulma, Eko Kusratmoko, Ratna Saraswati
Coastal Physical Vulnerability Of Surabaya And Its Surrounding Area To Sea Level Rise, Sayidah Sulma, Eko Kusratmoko, Ratna Saraswati
Makara Journal of Technology
The study for coastal vulnerability to sea level rise was carried out in Surabaya and its surrounding area, it has focused on calculations of the physical vulnerability index were used coastal vulnerability index (CVI) methods. It was standardized by the multi criteria analysis (MCA) approach according to the study area. The score of each physical variable derived from remote sensing satellite data and the results of studies that have been done, such as modeling results and thematic maps, and then integrated into geographic information systems (GIS). Result of this study shows that the coastal areas of Gresik, Surabaya, and Sidoarjo …
The Effect Of Size And Crumb Rubber Composition As A Filler With Compatibilizer Pp-G-Ma In Polypropylene Blends And Sir-20 Compound On Mechanical And Thermal Properties, Erna Frida
Makara Journal of Technology
Having been researched the development of thermoplastic elastomer material of polypropylene and natural rubber SIR- 20 compound with Crumb Rubber as the filler. Reinforced polypropylene with size 60 mesh with 1 mm, and the composition of the Crumb rubber (30, 40, and 50) wt%. Observed mechanical properties are tensile strength, fracture elongation, Young's modulus, tear strength and impact strength. Thermal properties are analyzed by DSC and DTA/TGA. It is acquired that for the size of 60 mesh crumb rubber tensile strength, fracture elongation, Young’s modulus, tear strength and impact strength are bigger than 1mm size. The addition of 60 mesh …
Development Of Local-Economic-Development Small And Medium Industries (Led-Sme) In East Java, Rachmad Hidayat, Sabarudin Akhmad
Development Of Local-Economic-Development Small And Medium Industries (Led-Sme) In East Java, Rachmad Hidayat, Sabarudin Akhmad
Makara Journal of Technology
This paper presents the effects of Indonesian government’s developmental efforts of assistance and training performed on the growth of LED-SME business units and business performance. Both parameters of the government’s assistance and training were used to analyze the impact to the growth and performance of business unit. To achieve a comprehensive result, samples acquired in this research were about 190 entrepreneurs and managers of LED-SME from East Java. Based on the parameters above, there are five hypotheses made to prove the relationship of the assistance and training to the growth and performance of business units. The structural equation modeling (SEM) …
Cdm Potential In Palm Solid Waste Cogeneration As An Alternative Energy In Aceh Province, Mahidin Mahidin, Izarul Machdar, Muhammad Faisal, Muhammad Nizar
Cdm Potential In Palm Solid Waste Cogeneration As An Alternative Energy In Aceh Province, Mahidin Mahidin, Izarul Machdar, Muhammad Faisal, Muhammad Nizar
Makara Journal of Technology
Empty Fruit Bunch (EFB) as a solid waste in Crude Palm Oil (CPO) industry does not utilized yet as an alternative energy source to generate electricity. It is well known that use of solid wate (biomass) as an energy source is part of the Clean Development Mechanism (CDM) scheme due to direct reduction of Green House Gases (GHGs) emission and provide a direct contribution to sustainable development. Utilization of EFB as a source of energy is very potential to be implemented in Aceh since this province has 25 CPO Mills at the moment which actively produce about 870,000 ton EFB …
Small Scale Experiment: Thermal Performance Comparison Between Fiber-Cement Roof And Photovoltaic Roof In Malang, Indonesia, Nurhamdoko Bonifacius, Sri Nastiti Nugrahani Ekasiwi
Small Scale Experiment: Thermal Performance Comparison Between Fiber-Cement Roof And Photovoltaic Roof In Malang, Indonesia, Nurhamdoko Bonifacius, Sri Nastiti Nugrahani Ekasiwi
Makara Journal of Technology
Irradiation on the surface of photovoltaic module heats up the photovoltaic module itself and the room underneath the roof of integrated photovoltaic building in the tropics area. Room heating reduces thermal condition and photovoltaic module surface heating reduces its performance in generating electricity. This paper discusses an experiment of measuring the surface temperature of photovoltaic modules and fiber-cement roof surface as a comparison. This experiment also measures the impact of rising temperatures in each space underneath. It used small-scale mock-ups exposed to direct sunlight. The result of the experiment shows that photovoltaic roof surface temperature is lower than fiber-cement roof …
Improved Optical Probe For Measuring Phytoplankton Suspension Concentrations Based On Optical Fluoresensce And Absorption, Retno Wigajatri Purnamaningsih, Nining Betawati Prihantini
Improved Optical Probe For Measuring Phytoplankton Suspension Concentrations Based On Optical Fluoresensce And Absorption, Retno Wigajatri Purnamaningsih, Nining Betawati Prihantini
Makara Journal of Technology
This paper discusses the results of improved optical probe that works according to optical fluorescence and absorption phenomena for measuring the phytoplankton suspension concentrations. Measurements are made on the Scenedesmus sp. culture. The laboratory test has shown that range of concentration from 104 up to around 1 x 106 cells/mL; fluorescence intensity at λ = 685 nm; and logarithmic of transmission intensity at λ = 405 nm are proportional to the cell concentration linear with proportional constant γ = 4 × 10-5 and β = –2 × 10-7 mL/cell respectively.
Mechanical And Thermal Properties Of Polypropylene Reinforced By Calcined And Uncalcined Zeolite, Nurdin Bukit
Mechanical And Thermal Properties Of Polypropylene Reinforced By Calcined And Uncalcined Zeolite, Nurdin Bukit
Makara Journal of Technology
This study was carried out to compare mechanical and thermal properties of polypropylene (PP) reinforced with uncalcined and calcined zeolites. The PP samples were reinforced with zeolites at various quantities of 2, 4, and 6 (wt %). The comparison of the two types of zeolite was based on mechanical properties, including tensile strength, elongation at break, and Young’s modulus, and thermal characteristics analyzed using DSC, and DTA/TGA technique. The results obtained clearly revealed that both zeolites were able to significantly increase tensile strength and Young’s modulus of the samples, with calcined zeolite was found to work better. Addition of calcined …
Benchmark For Country-Level Earthquake Strong-Motion Instrumentation Program, Widjojo Adi Prakoso, I Nyoman Sukanta
Benchmark For Country-Level Earthquake Strong-Motion Instrumentation Program, Widjojo Adi Prakoso, I Nyoman Sukanta
Makara Journal of Technology
An empirical study to develop benchmark models at country-level to assess the suggested number of earthquake strongmotion stations based on a framework encompassing geographic, demographic, and socio-economic parameters is reported. The models are to provide a working estimate of the required number of stations for improving the strongmotion instrumentation program of Indonesia. National earthquake strong-motion networks of New Zealand, Japan, Taiwan, Iran, Turkey, and Italy were used as the references. The parameter proposed is the number of stations in land area of 1,000 km2, and three models based on the exponential regression analysis are presented as functions of population density, …
Worst Case Of Relative Disturbance Gain Array For Uncertain Distillation System, Rudy Agustriyanto, Jie Zhang
Worst Case Of Relative Disturbance Gain Array For Uncertain Distillation System, Rudy Agustriyanto, Jie Zhang
Makara Journal of Technology
This article discusses the constrained nonlinear optimization formulation for calculating the worst case of lower and upper bounds of relative disturbance gain array (RDGA) for uncertain process models. The proposed approach seeks the minimum and maximum values of the relative disturbance gains subject to the constraints in which the process and disturbance gains are within their uncertainty ranges. RDGA ranges are useful for control structure determination and the related robustness, as they provide information regarding the sensitivity to gain uncertainties. The proposed method is demonstrated by ternary distillation column case study. Closed loop simulation results support the analysis based on …
Biodiesel Production From Waste Cooking Oil Using Hydrodinamic Cavitation, Muhammad Dani Supardan, Satriana Satriana, Mahlinda Mahlinda
Biodiesel Production From Waste Cooking Oil Using Hydrodinamic Cavitation, Muhammad Dani Supardan, Satriana Satriana, Mahlinda Mahlinda
Makara Journal of Technology
The aim of this research was to study biodiesel production from low cost feedstock of waste cooking oil (WCO) using hydrodynamic cavitation apparatus. A two-step processes esterification process and transesterification process using hydrodynamic cavitation for the production of biodiesel from WCO is presented. The first step is acid-catalyzed esterification process for reducing free fatty acid (FFA) content of WCO and followed by base-catalyzed transesterification process for converting WCO to biodiesel as the second step. The result of esterification process with methanol to oil molar ratio of 5 and temperature of 60 oC showed that the initial acid value of WCO …
Knowledge Dictionary For Information Extraction On The Arabic Text Data, Wahyu Syaifullah Jauharis Saputra, Agus Zainal Arifin, Anny Yuniarti
Knowledge Dictionary For Information Extraction On The Arabic Text Data, Wahyu Syaifullah Jauharis Saputra, Agus Zainal Arifin, Anny Yuniarti
Makara Journal of Technology
Information extraction is an early stage of a process of textual data analysis. Information extraction is required to get information from textual data that can be used for process analysis, such as classification and categorization. A textual data is strongly influenced by the language. Arabic is gaining a significant attention in many studies because Arabic language is very different from others, and in contrast to other languages, tools and research on the Arabic language is still lacking. The information extracted using the knowledge dictionary is a concept of expression. A knowledge dictionary is usually constructed manually by an expert and …
Stress Corrosion Cracking Susceptibility Of Ultrafine Grained Az31, G. R. Argade, W. Yuan, K. Kandasamy, R. S. Mishra
Stress Corrosion Cracking Susceptibility Of Ultrafine Grained Az31, G. R. Argade, W. Yuan, K. Kandasamy, R. S. Mishra
Materials Science and Engineering Faculty Research & Creative Works
In this study, stress corrosion cracking (SCC) behavior of AZ31 magnesium alloy was carried out using slow strain rate testing (SSRT) technique in 3.5 wt.% NaCl solution. the influence of microstructural scale on the stress corrosion behavior was investigated in AZ31 alloy with three different mean grain sizes. Single-pass and two-pass friction stir processing (FSP) was employed to obtain fine grain and ultrafine grain microstructures, respectively. for FSP, SSRT specimens were extracted from the processed region. SSRTs were carried out in air and solution at an initial strain rate of 10 -6/s. a significant decrease in the ultimate tensile strength …
Graphene Refinement By High Temperature Anneals, Benjamin A. Calvopina, Justin Bult, Jeff Blackburn
Graphene Refinement By High Temperature Anneals, Benjamin A. Calvopina, Justin Bult, Jeff Blackburn
STAR Program Research Presentations
Graphene’s intrinsic properties of being a good conductor as well as having efficient optical transmission make it a potentially useful material in photovoltaic cells as a transparent conducting electrode. One problem preventing graphene from being fully utilized stems from contaminates created and deposited during the transfer process of multiple graphene layers. After synthesis, TRT (Thermal Release Tape) is applied to the graphene supported on the copper growth substrate. TRT utilizes a unique formulation of adhesive that is temperature sensitive so that it will release when heated. Upon removing the growth substrate in a chemical bath, the TRT is used to …
Selective Laser Sintering; A Design Of Experiments, Philip David Hopkins, Victor Castillo Phd
Selective Laser Sintering; A Design Of Experiments, Philip David Hopkins, Victor Castillo Phd
STAR Program Research Presentations
Additive Manufacturing (AM), also commonly known as 3D Printing or Rapid Prototyping, is a method of manufacturing that provides for the ability to make intricate internal features and easily customizable parts. The concept is to break a Computer Aided Design (CAD) file into a series of thin layers that are sent to the machine and laid down one layer at a time. Just like any other form of processing, material properties can alter by undergoing this process. Manipulating various parameters of the AM process can allow for different properties to be achieved. For this reason, an in depth study will …
Magnetic Properties Study Of The Mn-Al System With Additions Of B Or C And Mechanical Milling Techniques, Timothy E. Prost
Magnetic Properties Study Of The Mn-Al System With Additions Of B Or C And Mechanical Milling Techniques, Timothy E. Prost
Department of Engineering Mechanics: Dissertations, Theses, and Student Research
Recently a shift in the focus of permanent magnetic research has moved from Rare Earth (RE)-based alloys to those made from more readily available elements. Because of their relatively large magnetocrystalline anisotropy, L10 compounds have the potential for use as permanent magnet materials. One particular alloy that is readily available and inexpensive is near equi-atomic manganese and aluminum (Mn50-Al50). First characterized in 1958, it did not receive much attention until more recently when RE supply chain issues made the alloy more attractive for commercial and research applications. The ferromagnetic (FM) τ-phase (L10) is …
Dynamical Properties Of Ferroelectric Perovskites (Ba,Sr)Tio3 And Pb(Zr,Ti)O3 Systems From First Principles, Jeevaka Weerasinghe
Dynamical Properties Of Ferroelectric Perovskites (Ba,Sr)Tio3 And Pb(Zr,Ti)O3 Systems From First Principles, Jeevaka Weerasinghe
Graduate Theses and Dissertations
A first-principles-based effective Hamiltonian scheme which incorporates coupling between ferroelectric (FE) and antiferrodistortive (AFD) motions is applied to Pb(Zr,Ti)O3 alloys. It validates the existence of two modes of E symmetry (rather than the single E(1TO) soft mode) in the 50-75 cm-1 range for temperatures smaller than 200 K and for compositions falling within the Rhombohedral R3c phase. Coupling between long-range-ordered FE and AFD motions is shown to be the cause of the additional mode and more insight into its nature is provided. This scheme is further used to reveal a field-induced anticrossing involving FE and AFD degrees of …
Transition Of Deformation Behavior In An Ultrafine Grained Magnesium Alloy, S. K. Panigrahi, K. Kumar, N. Kumar, W. Yuan, R. S. Mishra, R. Delorme, B. Davis, R. A. Howell, K. Cho
Transition Of Deformation Behavior In An Ultrafine Grained Magnesium Alloy, S. K. Panigrahi, K. Kumar, N. Kumar, W. Yuan, R. S. Mishra, R. Delorme, B. Davis, R. A. Howell, K. Cho
Materials Science and Engineering Faculty Research & Creative Works
The deformation behavior of friction stirs processed magnesium alloy with average grain size ranging from 25 μm to 240 nm was studied. an evaluation of critical grain size for transition of deformation mode from twinning to slip was carried out by employing tensile and compressive tests. the role of critical grain size in transition of deformation behavior from strain hardening to softening was established. Inhomogeneous yielding was observed during tensile test of ultrafine-grained magnesium alloy below the critical grain size. © 2012 Elsevier B.V.
Rapid Oxidation Of Titanium And Its Alloys, Monica A. Cadena, Stephen Stafford
Rapid Oxidation Of Titanium And Its Alloys, Monica A. Cadena, Stephen Stafford
COURI Symposium Abstracts, Summer 2012
The tragedy of the Space Shuttle Columbia demonstrated the need for better understanding of materials in extreme environments. This study’s main objective was to provide more information about the behavior of materials, particularly Ti-6Al-4V, whenever conditions (such as temperature, pressure and behavior) change dramatically. The study included the microstructural analysis of Ti-6Al-4V samples that were exposed to conditions that approximate those encountered during re-entry by arc-jet experimentation. The analysis of these samples consisted of scanning electron microscopy and x-ray diffraction. The x-ray diffraction analysis showed the presence of several titanium oxides, such as Ti3-O and Ti6-O on different sections of …
Effects Of Annealing/Solution Treating And Aging On Longitudinal And Transverse Properties Of Ti-6al-4v Forgings, Blake Reller
Effects Of Annealing/Solution Treating And Aging On Longitudinal And Transverse Properties Of Ti-6al-4v Forgings, Blake Reller
Materials Engineering
Forty-eight subsize round-bar tensile samples (ASTM E8) were machined from 3-in-thick forgings of Ti-6Al-4V. Half of these samples were cut so the axis aligned with the longitudinal (LG) direction of the forging, the other half were cut to align with the transverse (LT) direction. Four samples from each direction were subjected to one of six heat treatments so that a total of eight samples received each treatment. Annealed samples were held at 1350°F for two hours, then air cooled. Solution treated and aged (STA) samples were solution treated at one of five temperatures between 1785°F and 1435°F for one hour …
Effect Of Oxidation On Weld Strengthof Dissimilar Resistance Weld Interface Between 304 Stainless Steeland Near Equiatomic Austenitic Nitinol Guide Wire, Matthew Rudow
Master's Theses
Abbott Vascular encountered strength and variability issues when attempting to resistively weld 304 Stainless Steel to equiatomic Nitinol. Initial observations suggested that passivation layer (Cr2O3, TiO2) formation affected the weld interface. One hundred 304 Stainless Steel/Nitinol pairs were allowed to oxidize in air at room temperature for allowed periods of time (.1, 1, 3, 5, 7, 12, 16, 24, 168, and 336 hours). Each pair was welded resistively with constant current. A Miyachi/Unitek Advanced Data Analysis Monitor (ADAM) recorded the peak resistance at the instance the weld was made. Resistances were compared to Instron …
Characterization And Analysis Of Low Room Temperature Ductility Nickel-Based Superalloy 718 Plus For Aircraft Engine Forgings, Jonathon Bracci
Characterization And Analysis Of Low Room Temperature Ductility Nickel-Based Superalloy 718 Plus For Aircraft Engine Forgings, Jonathon Bracci
Materials Engineering
Schlosser Forge Co. forges low pressure turbine (LPT) cases from the nickel based superalloy 718 Plus using the ring rolling forging process. Schlosser has been experiencing low room temperature ductility problems in a number of their 718 Plus LPT cases. LPT cases are required to pass a 4D tensile test at room temperature with a minimum of 15 percent elongation. The ductility problem was reduced by increasing the forging temperature from 1825˚F to 1850˚F. Analysis was performed on 718 Plus samples taken from forged LPT cases that failed the room temperature ductility requirement and ones that passed the requirement. The …
Effects Of Beta Stabilizers On Quench Delay Susceptibility Of Ti-6al-4v, Kyle Logan
Effects Of Beta Stabilizers On Quench Delay Susceptibility Of Ti-6al-4v, Kyle Logan
Materials Engineering
Tensile samples of Titanium 6Al-4V (Ti-6Al-4V) were machined from forgings containing rich and poor amounts of beta stabilizers in their compositions. The tensile samples were each heat treated two times. In the first round of heat treatments, the samples were either beta solution treated (BST), or solution treated (ST). Each sample was water quenched with varying quench delays of 10, 20, and 30 seconds. BST treated specimens were then overaged at 1350°F for 2 hours and air cooled (BSTOA); while the ST treated samples were aged at 990°F for 6 hours and air cooled (STA). Following heat treating, the tensile …
Microstructural Characterization Of Ti-6al-4v And Its Relationship To Sample Geometry, Blake Gaspar
Microstructural Characterization Of Ti-6al-4v And Its Relationship To Sample Geometry, Blake Gaspar
Materials Engineering
A problem exists with a part produced by forging made by Shultz Steel of Ti-6Al-4V in the variance of properties throughout the part. There is one specific region that exhibits the most variance. The purpose of the report is to determine any microstructural differences within the region of interest in the part. When microstructures of the inner section and outer section of the part were looked at it was determined that they exhibited a martensitic structure. There was a noticeable difference in the lath structure between sections. The outer region contained larger more widely spread laths of an average length …