Materials Science and Engineering Commons^™

Effect Of K2o/Sio2 Ratio On The Crystallization Of Leucite In Silicate-Based Glasses, P Sooksaen, J Boonmee, C Witpathomwong, S Likhitlert

Journal of Metals, Materials and Minerals

Leucite-based glass-ceramics were prepared by controlled crystallization of suitable glass compositions to give required crystalline phase/s. Three glass batches in the system SiO2 - K2O - NaO2 - Al2O3 - TiO2 - CaO were prepared by varying K2O/SiO2 ratio, then melted and quenched. Glasses were characterized for onset of crystallization temperatures by differential thermal analysis (DTA), and heat treatments were carried out from 850 - 1000°C for 4 hours for controlled crystallization of leucite phase. Physical, chemical and crystal structure characterizations were carried out using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). XRD found …

Effect Of Chitosan's Molecular Weights On Mangosteen Dye Fixation On Cotton Fabric, C Suitcharit, F Awae, W Sengmama, K Srikulkit

Journal of Metals, Materials and Minerals

The effect of chitosan's molecular weights (Mw) on mangosteen dye fixation on cotton was studied using chitosans with Mw of 226 kDa (CTS-Mw I; native chitosan), 10.8 kDa (CTS-Mw II), and 7.2 kDa (CTS-Mw III). The preparation of chitosan with different Mws was carried out using sodium nitrite in acid media (depolymerization process). The obtained chitosans were applied onto cotton fabric. The effect of chitosan concentrations on fixation and fastness properties of mangosteen dye extract was studied. The results showed that an increase in concentrations of depolymerized chitosans (CTS-Mw II and III) yielded an increase in N% contents. Nonetheless, the …

Pickling Kinetics Of Tertiary Oxide Scale Formed On Hot-Rolled Steel Strip, Y Jatuphaksamphan, N Phinichka, K Prapakorn, M Supradist

Journal of Metals, Materials and Minerals

During hot rolling process a steel strip covers with oxide scales. These scales have to be removed by acid pickling process. This work focuses on the study of the scale removing rate of a hot-rolled steel strip in order to find an expression explaining the rate of reaction in hydrochloric acid. The study of scale removal is accomplished by utilizing the pickling simulator with different acid concentrations and pickling temperatures. There are two approaches that can be used to find a scale removing rate; the measurement of weight change and the iron concentration change after the pickling process. In this …

Preparation Of Hydrophobic Chitosan Using Complexation Method For Pla/Chitosan Blend, P Chouwatat, P Polsana, P Noknoi, K Siralertmukul, K Srikulkit

Journal of Metals, Materials and Minerals

In this study, dioctyl sulfosuccinate-chitosan complex was prepared by a mechanical mixing of aqueous chitosan with sodium dioctyl sulfosuccinate. As a result, hydrophobic chitosan was achieved. Characterizations of the complex were carried out including XRD, TGA, and FT-IR in order to follow changes in the chitosan structure. Thus produced chitosan complex was hydrophobic and anticipated to be compatible with PLA. Solution blending of PLA and hydrophobic chitosan was then conducted. Characterization techniques including XRD and FT-IR were employed to investigate the structure of the polymer blend. FTIR spectra showed that changes in the fingerprint of the chitosan amide band in …

Thermal Analysis Of Fe-Carbide And Fe-C Mixtures, R Tongsri, B Vetayanugul

Journal of Metals, Materials and Minerals

Differential thermal analysis (DTA) was employed to monitor changes which occurred during heating of Fe-carbide and Fe-C mixtures. The DTA curves showed a relationship between endothermic peaks and phase transformations given in the Fe-C phase diagram. The transformations included (i) magnetic Fe to non-magnetic Fe, (ii) pure α-Fe to pure γ-Fe, (iii) γ + Fe3C → Liquid and (iv) pure γ-Fe to pure δ-Fe. Melting of the Fe-SiC powder compacts when sintered at temperatures higher than 1200°C was revealed and indicated by the endothermic peak of 1230°C. This peak corresponded to the transformation of γ + Fe3C → Liquid. That …

Effects Of Replacing Binder With Powder Space Holder On Properties Of Metal Injection Moulded Foam, U Koikul, A Manonukul, S Suranuntchai

Journal of Metals, Materials and Minerals

Metal foam can be produced using metal injection moulding with powder space holder. In this study, the effects of volume fraction of spacer holder on the foam properties were studied. Spherical poly (methyl methacrylate) (PMMA) particles were used as a space holder material. The 30% volume fraction of stainless steel 316L powder was mixed with varied volume fractions of binder and PMMA. There were five volume fractions of PMMA, namely 30% to 50%, with an increment of 5%. The results showed that the volume fraction of PMMA affected the properties. As the volume fraction of PMMA increased, the number of …

Study Of Covering Conditions For Sintering Of Metal Injection Moulded Commercially Pure Titanium, N Muenya, A Manonukul

Journal of Metals, Materials and Minerals

In metal injection moulding process, sintering for some specific materials is different from general materials. Titanium is a material that is not easy to sinter because it is a very reactive metal at high temperature. The high quality of the titanium component is difficult to control, especially so in point of the levels of carbon and oxygen, which have large effects on the mechanical properties. Commercially pure titanium was injected, debinded and sintered at 1150°C and 1250°C in high vacuum without a cover, and with a quartz cover, a mullite cover and an alumina cover, respectively. From the physical and …

Utilization Of Fly Ash From Power Plant For Adsorption Of Hydrocarbon Contamination In Water, J Sasithorn, D Wiwattanadate, S Sangsuk

Journal of Metals, Materials and Minerals

Adsorption efficiency of polycyclic aromatic hydrocarbons (PAHs) contamination in water with rice husk fly ash from a power plant was investigated in comparison with coal fly ash and silica from rice husk fly ash, with and without surface treatment. Naphthalene was used as a representative for PAHs, and Cethyltrimethylammoniumbromide (CTAB) was used as surface treating agent for the present study. Various factors, such as shaking rate, shaking time, pH of naphthalene aqueous solution, and adsorbentnaphthalene weight ratio, were investigated to identify the optimum condition for each adsorbent. Upon using 0.3 g adsorbent in 100 ml of 10 mg/l naphthalene solution, …

An Investigation Of Microstructural Change Of Low Alloy Steel Aisi 4150 By Seebeck Coefficient, T Samran, P Termsuksawad

Journal of Metals, Materials and Minerals

Low alloyed steels, whose hardness can be modified by heat treatment, have been widely used in various applications. After heat treatment, they are normally destructively characterized and tested by many approaches via optical microscope and hardness testing. It is useful to develop a non-destructive method relating to its properties and microstructures. The proposed non-destructive approach in this study is the Seebeck coefficient measurement. The materials in this study were carbon steels AISI 4150 rod with a diameter of 1.3 cm and length of 3 cm. The specimens were heat-treated at 900ºC for 1 hour and were then cooled to room …

Study Of Process Parameters In Conventional Powder Metallurgy Of Silver, S Amaranan, A Manonukul

Journal of Metals, Materials and Minerals

Compaction, sintering and physical properties of silver powder were investigated. The silver powder was uniaxially compacted into a cylindrical specimen using compaction pressures of 13.79, 27.58, 41.37 and 55.16 MPa. Compacted parts were sintered at 700, 800 and 900°C in argon atmospheres. In addition, compacted parts were also sintered in vacuum at 900°C. For the sintering temperatures of 700 and 800°C, it was found that the sintered density increased as the compaction pressure increased below 40 MPa, while the sintered density decreased at a compaction pressure above 40 MPa. At the sintering temperature of 900°C, the sintered density decreased with …

Boron Carbide Based Solid State Neutron Detectors: The Effects Of Bias And Time Constant On Detection Efficiency, Nina Hong, John Mullins, Keith Foreman, Shireen Adenwalla

Shireen Adenwalla Papers

Neutron detection in thick boron carbide(BC)/n-type Si heterojunction diodes shows a threefold increase in efficiency with applied bias and longer time constants. The improved efficiencies resulting from long time constants have been conclusively linked to the much longer charge collection times in the BC layer. Neutron detection signals from both the p-type BC layer and the n-type Si side of the heterojunction diode are observed, with comparable efficiencies. Collectively, these provide strong evidence that the semiconducting BC layer plays an active role in neutron detection, both in neutron capture and in charge generation and collection.

Feasibility Of Manipulating Correlated Color Temperatures With A Phosphor Converted High-Powered Light Emitting Diode White Light Source, Matthew Michael Little

Master's Theses

In this thesis we examine the feasibility of developing a white light source capable of producing colors between 2500 and 7500 Kelvin on the black-body radiator spectrum by simply adjusting amperage to a blue and ultraviolet (UV) light emitting diode (LED). The purpose of a lighting source of this nature is to better replicate daylight inside a building at a given time of day. This study analyzes the proposed light source using a 385 nm UV LED, a 457 nm blue LED, a 479 nm blue LED, a 562 nm peak cerium doped yttrium aluminum garnet (YAG:Ce) phosphor, and a …

The Effects Of Carbon, Boron And Vanadium On The Microstructural Evolution And Hardness Of Steel-Based Hardfacing Alloys, Kyle Rafa

Materials Engineering

Current hardfacing alloys provide insufficient wear resistance due to either cracking or significant material wear. To increase wear resistance of steel-based hardfacing alloys, the effects of composition on microstructure and hardness were investigated in a progression of alloys. Initially, seven new alloys were prepared varying the carbon-boron ratio with the total constant at 3 wt%. Small arc-melt cast circular ingots were produced roughly 1 x 0.5 inches. Metallography provided insufficient phase magnification, thus a SEM equipped with EDS was used, allowing for microstructure and phase composition analysis. Four distinct carbide phases were found and image analysis software allowed for carbide …

The Characterization And Analysis Of In-Vitro And Elevated Temperature Repassivation Of Ti-6al-4v Via Afm Techniques, Aaron J. Guerrero

Master's Theses

ABSTRACT

The Characterization and Analysis of In-vitro and Elevated Temperature Repassivation of

Ti-6Al-4V via AFM Techniques

Aaron J Guerrero

Research in the corrosion of orthopaedic implants is a growing research field where implants have been known to show adverse effects in patients who have encountered the unfortunate dissolution of their implants due to corrosion. Once corrosion begins within the body, many adverse biological reactions can occur such as late on-set infections resulting in severe health complications. The focus of this research is specifically related to the problem of late on-set infections caused by localized corrosion of orthopaedic implants. In medical …

Design, Fabrication, Structural Testing, And Numerical Analysis Of A Small Scale Composite Wing, Jacob David Gaunt, Juan Carlos Flores, Vincent Andrew Perry

Aerospace Engineering

A small scale composite wing based on a design found on an experimental aircraft was designed, constructed, and tested dynamically and statically. The wing was constructed similarly to an experimental aircraft wing. The performed static test was intended to produce pure bending. Strain gages were used to measure strains on the wing structure. The strains were converted to stresses to aid in analysis. The static test results suggested that the wing was actually under torsion. Four structural modes were found from the static test. A finite element analysis model was made to compare experimental results to numerical analytical results. The …

Irrigation Leak Detection: Using Flow Rate Sensors To Detect Breaks In An Irrigation System, Adam Openshaw, Kalvin Vu

Computer Engineering

This report details the exploration and invention of a mechanism that can detect breaks in an irrigation system. With the ultimate goal of conserving water, we have designed an inexpensive, self sustaining flow rate monitor that can be used to identify anomalies in an irrigation system and wirelessly communicate the status of the system to a base station. Our implementation can also determine the direction of the anomaly based on the nature of the anomaly itself. This means that multiple monitors can be used to pinpoint the location of a break within the system in addition to merely detecting its …

Characterization Of Aluminum-Boron Carbide Particulate Metal Matrix Composites, Eric Blank

Materials Engineering

The analysis of die-cast 380 aluminum-boron carbide particulate metal matrix composites (MMC) was performed in order to see if the samples had the required tensile strength of 300 MPa. 10wt% B4C die-cast samples were produced and tested. Half were heat treated to the T6 condition and the others were left as cast. Using ASTM standard B 557M it was found that the average tensile strength for the as-cast samples was 130 MPa and the heat treated samples had a tensile strength of 93 MPa. These values were both lower than expected. The heat treated samples were not expected to have …

Effects Of A Solution Anneal Quench Delay On The Heat Treatment Response Of Aluminum 2219-T6, Daniel James Filomeo

Materials Engineering

The ageing response for aluminum 2219-T6 was investigated to determine the effects a quench delay (QD) could have on tensile properties. Before testing commenced, furnace surveys were conducted to ensure they could meet the required temperature stability of + 10˚F (+6˚C). MIL-H-6088 specified a maximum quench delay of 15 seconds for parts thicker than 2.29 mm (0.090 in). An investigation was conducted on how different quench delay times changed the ageing response of T6 heat treated for Al 2219. Heat treatments were performed according to the ASM Handbook. Preliminary tests were performed on 1-1.5 in. cube blocks of Al 2219 …

Validation Of A Secondary Fabric Supplier And Characterization Of Alternate Cores For Use In The Aptera 2e Sandwich Core Composite, Bryan Rogers

Materials Engineering

Polymer matrix composites’ high strength to weight ratio has made them an ideal material choice for use in lightweight transportation vehicles. Aptera Motors, a company based out of Oceanside, CA, is currently developing a next-generation high efficiency passenger vehicle called the Aptera 2e. The 2e’s body is composed of a sandwich core composite containing laminates of E-glass fibers embedded within an epoxy matrix sandwiched between a polyester hexagonal core. This project looked to validate a secondary fabric supplier for use in Aptera’s composite and characterize the core shear properties of two alternate core materials for future iterations of Aptera’s vehicle. …

Enhanced Light Extraction Efficiency From Gan Light Emitting Diodes Using Photonic Crystal Grating Structures, Simeon S. Trieu

Master's Theses

Gallium nitride (GaN) light emitting diodes (LED) embody a large field of research that aims to replace inefficient, conventional light sources with LEDs that have lower power, higher luminosity, and longer lifetime. This thesis presents an international collaboration effort between the State Key Laboratory for Mesoscopic Physics in Peking University (PKU) of Beijing, China and the Electrical Engineering Department of California Polytechnic State University, San Luis Obispo. Over the course of 2 years, Cal Poly’s side has simulated GaN LEDs within the pure blue wavelength spectrum (460nm), focusing specifically on the effects of reflection gratings, transmission gratings, top and bottom …