Metallurgy Commons^™

The Role Of Si3n4 Amorphous Phase In Nc-Tin/A-Si3n4 Nanocomposites In Increases The Hardness And Thermal Stability, Keba Moto

Makara Journal of Technology

The role of Si3N4 amorphous phase in nc-TiN/a-Si3N4 nanocomposites will be shown and compared with polycrystalline ZrN/Ni which has no such amorphous phase (non-composites). The presence of amorphous phase Si3N4 increases the hardness of film as well as the toughness of the bulk nanocomposites under indentation load. It has been observed that nc-TiN/a-Si3N4 nanocomposites films has higher thermal stability than ZrN/Ni polycrystalline films.

Biodiesel's Characteristics Preparation From Palm Oil, Tilani Hamid. S, Rachman Yusuf

Makara Journal of Technology

Biodiesel’s characteristics preparation from palm oil. Using vegetable oils directly as an alternative diesel fuel has presented engine problems. The problems have been attributed to high viscosity of vegetable oil that causes the poor atomization of fuel in the injector system and pruduces uncomplete combustion. Therefore, it is necessary to convert the vegetable oil into ester (metil ester) by tranesterification process to decrease its viscosity. In this research has made biodiesel by reaction of palm oil and methanol using lye (NaOH) as catalyst with operation conditions: constant temperature at 60 oC in atmosferic pressure, palm oil : methanol volume ratio …

Development Of Hardness Measurement Procedure For Nanocomposite Nc-Tin/A-Si3n4, Keba Moto

Makara Journal of Technology

Hardness of nc-TiN/a-Si3N4 nanocomposites which was determined by using two methods of measurements i. e. depth sensing method and remaining plastic indentation area that were magnified by using SEM (Scanning Electron Microscope) lie in the good agreement. The hardness value is not influenced by the biaxial and residual compressive stress. The measurement of the biaxial stress on the substrate shows a very small value of biaxial stress as well as the constant hardness and crystallite size against annealing temperature. Therefore, the reported hardness value here is the intrinsic value that depend on its microstructure properties.

Design And Analysis For Melt Casting Metallic Fuel Pins Incorporating Volatile Actinides, Xiaolong Wu

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fundamental issues related to the selection of a metallic fuel casting furnace design are presented and discussed including heating mechanisms, casting issues, crucible design, and issues related to the mass transport of americium. The process of evaluating all of these different criteria is undertaken to select a concept that would have the greatest chance of success for casting americium in a metallic fuel rod. Based on this evaluation process, a concept for the casting of metallic fuel pins containing high vapor pressure materials is selected and discussed. The important physics of this concept include mass transport of americium from the …

Design And Analysis Of A Process For Melt Casting Metallic Fuel Pins Incorporating Volatile Actinides, Yitung Chen, Darrell Pepper, Randy Clarksean

Fuels Campaign (TRP)

UNLV has developed and will continue to develop process models for the analysis of melt casting processes. This work will continue to be performed under the guidance of Argonne National Laboratory (ANL) engineers to ensure that their knowledge and experience benefits the project. The research to be conducted during the second year will center on performing detailed analyses on a conceptual design of an inductively heated skull-crucible casting furnace. Processing conditions will be analyzed, basic models utilized, and detailed heat and mass transfer models will be developed to analyze the most promising processes. The goal of this second year is …

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase Ii, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Niobium cavities are important parts of the integrated NC/SC high-power linacs. Over the years, researchers in several countries have tested various cavity shapes. They concluded that elliptically shaped cells are the most appropriate shape for superconducting cavities. The need for very clean surfaces led to the use of a buffered chemical polishing procedure for surface cleaning to get good performance of the cavities. This proposal discusses the second phase of research in the second year of the project.

The first phase (starting Summer 2001) has resulted in improving the basic understanding of multipacting and the process of chemical etching. Based …

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements, Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada, Las Vegas (UNLV) and Idaho State University (ISU) is to evaluate the feasibility of determining residual stresses of welded (after pre-straining) engineering materials using a new nondestructive technique based on positron annihilation spectroscopy. The proposed technique is to use γ-rays 2 from a small MeV electron Linac to generate positrons inside the sample via pair production. This method can be used for materials characterization and investigation of defects in thick samples that could not be accomplished by conventional positron techniques or other nondestructive methods. The data generated will …

The Effect Of Temperature On The Optical Absorptive And Reflective Behavior Of Metals, Thomas A. Hunyady

Mechanical & Aerospace Engineering Theses & Dissertations

In the five decades since its invention, the laser has been used to commercially process materials in an increasingly diverse number of ways. The precise control over the delivery of the incident energy that is afforded by a laser allows for a wide variety of applications. All of these processes depend in some way on two important physical properties of the material being treated. These properties are known as the optical reflectivity and absorptivity of a material. The values of each of these properties are different for each material and are influenced by a number of factors, including surface roughness, …

Integrating Passenger And Modulo As Learning Tools For Collaborative Engineering Education, Kalamullah Ramli, Frank Schwarz, Stefan Werner, A Halim Shamsuddin, Axel Hunger

Makara Journal of Technology

The University of Indonesia (UI), Gerhard Mercator University (GMU), the Universiti Kebangsaan Malaysia (UKM) have agreed to cooperate as partners to develop a joint bachelor (3+1) and masters (1+1) degree, and collaborate in the research fi elds of multimedia- and internet-based learning and application level active networks. This paper describes the introduction of the Offshore Project and the extending of information technology applications to the partner institutions in this international cooperation which would very much enhance the operations of the new initiative in engineering education, which could provide students in far distance with more fl exible learning environment.

Study Effect Of Salt Washing Process On Content And Iodium Stability Of Salt, Nelson Saksono

Makara Journal of Technology

Effect of Salt Washing Process on Content and Iodium Stability of Salt. Salt washing process should increase the salt quality. It should clean the salt from sludge or clay and also reduce the impurity compound such as Mg, Ca and the reductor content. The objective of these reseach is to assess the effect of washing process on the content og hygroscopic impurities compound (Ca and Mg), and reductor content of salt. The research also investigate the water absorbing, pH, KIO3 content as function of time to obtain effect of washing process on KIO3 stability in salt. The experiment result shows …

Object Classfification In Computer Vision With Discriminant Analysis, Amir Hamzahan

Makara Journal of Technology

A robotic sensor system is always supported by a computer system called ‘computer vision’. The important concept of computer vision is object classfifi cation. In this study two algorithms for object classifi cation in this system will be compared. Firstly, A simple method that do not need complex computation and that considered as an informal method is called binary tree decision structure. This method is based on modest caracteristic decriptors of an object such as vertical line, horizontal line or ellipse line. Unfortunately this method has weakness in recognize an image that contaminated by a noise. Secondly, a more formal …

Making Alloys (Ti1 - Xalx) N Using Plasma Cvd Technique From Alcl3 Powder, H2 And N2 Gas ,With Solvent Ticl4, Keba Moto

Makara Journal of Technology

The substitution of Ti atoms by Al atoms in TiN lattice sites to form (Ti1-xAlx)N is clearly demonstrated by the coatings which were deposited on steel substrate and using plasma CVD technique. The presence of Al atoms in TiN lattice site is shown by means of XRD and EDX techniques: lattice parameters decreasing of TiN as the fraction of Al increases (XRD) and precipitation of hexagonal AlN phase (XRD) as the fraction of Al exceeding 0.8 (EDX). The hardness of these coating are just around 30 GPa, which is beyond the values reported in literatures.

Effects Of 0.25 % Mo (Molybdenum) Which Is Contained In The Ductile Cast Iron On Mechanical Properties Of Austempered Ductile Iron (Adi)., Nukman Nukman, Bustanul Arifin, Bambang Sugiarto

Makara Journal of Technology

The aim of this research is to investigate the effects of 0.25 % Mo (Molybdenum) which is contained in the ductile cast iron on mechanical properties of Austempered Ductile Iron (ADI). The various temperatures and the holding times are used in the heat treatment processes. Using a given 0.25 % Mo in the ductile iron, ADI's alloyed developes a higher ultimate tensile stress value and decreases the elongation if we compare with the as cast (non alloy ductile iron). The higher impact energy value obtained at 9000 C austenization and 375o C austempering temperatures during 60 minutes holding times. The …

The Manufacturing Properties Of Galvanised Steel Sheet With Hexagonal And Tetragonal Network Of Circle Holes, Rahmat Saptono

Makara Journal of Technology

Galvanized steel sheet of 0.8 mm in thickness was drilled with circle holes of 2.5 mm diameter and spacing arranged in tetragonal and hexagonal pattern. The manufacturing properties of specimen were studied through drawing and stretching simulative test. It was concluded from the results that, at high ratio of punch to hole diameter (40/2.5), the drawing properties (LDR) of both square and hexagonal perforated sheet were slightly lower than that of solid sheet, while hexagonal perforated showing LDR somewhat higher than the square one. The stretching properties (LDH) of sheet, however, were much lower than that of solid sheet while …

Develops The Software Of Dsp Processor For The Cdma Circuitry, Arman Djohan D.

Makara Journal of Technology

This research develops the software of DSP Processor type TMS320C54X for the CDMA circuitry. This research apply two algorithms namely Mathematic Algorithm and table lookup Algorithm. From both algorithms, the research examine what algorithm have the fasted processing time and the smallest memory occupation. From the examination results the Mathematic Algorithm have 20.62 milliseconds processing time and the Table lookup algorithm have 14.08 milliseconds processing time. The Table lookup algorithm have the fastest processing time because the Matematic algorithm need the rounding process of the fi gure. Eventhough such processing time is not exceed from the 125 millisecond of delay …

Fretting Fatigue Behavior Of A Titanium Alloy Ti-6al-4v At Elevated Temperature, Onder Sahan

Theses and Dissertations

The purpose of this research is to investigate the fretting fatigue behavior of the titanium alloy Ti-6Al-4V at elevated temperature is investigated. Fretting and plain fatigue experiments are conducted at 260 °C. Crack initiation location and crack initiation orientation is measured and fretting and plain fatigue life data of the specimens from these tests are obtained. Fatigue parameters capable of predicting the number of cycles to specimen failure, the crack location and the crack orientation along the contact surface are analyzed. The parameters are calculated by using the computed stresses and strains obtained from the finite element analysis. The mechanisms …

Modeling, Fabrication, And Optimization Of Niobium Cavities – Phase I: Quarterly Progress Report November 20, 2001 - February 20, 2002, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Multipacting is one of the major loss mechanisms in RF superconductivity cavities for accelerators. This loss mechanism limits the maximum amount of energy/power supported by the cavities. Optimal designs have been identified in others’ studies. In practice, these designs are not easily manufactured. Chemical etching processes used to polish the cavity walls result in a nonuniform surface etch. A nonuniform surface etch will leave some unclean areas with contaminants and micron size particles. These significantly affect multipacting. Further, a nonuniform etch will leave areas with damaged grain structure, which is not good for superconducting properties. Typically, the depth of chemical …

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase Ii Second Quarterly Report, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Niobium cavities are important parts of the integrated NC/SC high-power linacs. Over the years, researchers in several countries have tested various cavity shapes. They concluded that elliptically shaped cells are the most appropriate shape for superconducting cavities. The need for very clean surfaces lead to the use of a buffered chemical polishing produce for surface cleaning to get good performance of the cavities. Up to this point, the second phase has resulted in the design of an experimental setup for the fluid flow experiment. Other experimental activities include the evaluation of a vacuum system are underway. Little reportable progress has …

Modeling, Fabrication, And Optimization Of Niobium Cavities, Robert A. Schill Jr., Mohamed Trabia, Yitung Chen

Transmutation Sciences Materials (TRP)

All technologies for the transmutation of nuclear waste require a large source of neutrons. One of the principal methods of generating these neutrons is by using a particle accelerator to bombard a heavy metal target. One of the more promising designs for particle accelerators for transmutation systems is the Superconducting Radio Frequency (RF) high-current linear accelerator (linac). The power supplies for these systems have three major components: niobium cavities, power couplers, and cryomodules. This research project will develop models to predict the behavior and performance of the niobium cavities, which will then be used to design and optimize the superconducting …

Modeling, Fabrication, And Optimization Of Niobium Cavities – Phase I: Quarterly Progress Report August 20, 2001 - November 20, 2001, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Multipacting is one of the major loss mechanisms in rf superconductivity cavities for accelerators. This loss mechanism limits the maximum amount of energy/power supported by the cavities. Optimal designs have been identified in others’ studies. In practice, these designs are not easily manufactured. Chemical etching processes used to polish the cavity walls result in a nonuniform surface etch. A nonuniform surface etch will leave some unclean areas with contaminants and micron size particles. These significantly affect mutipacting. Further, a nonuniform etch will leave areas with damaged grain structure, which is not good for superconducting properties. Typically, the depth of chemical …

Modeling, Fabrication, And Optimization Of Niobium Cavities – Phase I: Quarterly Progress Report May 15, 2001 - August 15, 2001, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Multipacting is one of the major loss mechanisms in rf superconductivity cavities for accelerators. This loss mechanism limits the maximum amount of energy/power supported by the cavities. Optimal designs have been identified in others’ studies. In practice, these designs are not easily manufactured. Chemical etching processes used to polish the cavity walls result in a nonuniform surface etch compromising the optimal geometrical design. Past multipacting studies have not examined the impact of wall perturbations.

It is the purpose of this study to examine the chemical etching process in the design of niobium cavities so to maximize the surface quality of …

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase I, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Niobium cavities are important parts of the integrated NC/SC high-power linacs. Over the years, researchers in several countries have tested various cavity shapes. They concluded that elliptically shaped cells and buffered chemical polishing produce good performance. The objective of the proposed research is to maximize the performance of the niobium cavities through studying multipacting, studying the effect of chemical etching on the surface roughness, and redesigning the cavities.

The US Congress has recently authorized exploring an alternative way to deal with spent nuclear fuel: Accelerator Transmuting of Waste (ATW). In this approach, a particle accelerator produces protons that react with …

Relationship Between Cost Of Technical Training And Cost Reduction Of Internal Defects At John Deere Waterloo Foundry, John Brackin

Graduate Research Papers

Can the cost of technical training at John Deere Waterloo Foundry pay for itself in the reduction of internal defects? This research compared training costs to the savings from reduced internal defects on Molding Unit 801 located in the John Deere Waterloo Foundry. Training was the independent variable of this research. The results of this research identified a correlation between training costs ( operational definition on page 10) and defect reduction costs. A correlation between these two established a break even point for training dollars spent.

The dependent variable was the dollar savings based on reduction of internal defects. There …

An Evaluation Of The Aws Entry Level Welder Training Program, John R. Rice

Dissertations and Theses @ UNI

The purpose of this study was to evaluate the effectiveness of a training program for Entry Level Welders and to provide this information to the American Welding Society (AWS), industry, and educators. The problem of this study was to evaluate the AWS Entry Level Welder Training Program (ELWTP) by obtaining the opinions of faculty members who taught the program and welders who had completed the program.

Two groups comprised the research population for this study. The first group consisted of faculty members who were actually involved in teaching the course at institutions accredited by the AWS to offer the curriculum. …

A Fluid Flow Analysis Of Aluminum 356.0 In The Vacuum Assisted Countergravity Method, John Launstein

Graduate Research Papers

The purpose of this study is to determine the fluid flow pattern obtained through the use of the countergravitaional process. The physical fluid flow model assists design engineers in their casting design of parts utilizing the LS-Vac technology thereby reducing tooling costs and time losses.

A Comparison Of Tool Life Of Two Coated Carbide Inserts Under Identical Conditions And At Different Cycle Times, Garold Zander

Graduate Research Papers

Coated hardmetals have brought tremendous increases in productivity since 1969, when they were first applied to cutting materials. These coatings are extremely hard and are very abrasion resistant. Typical coatings are alumina oxide, silicon nitride with metal oxides, titanium carbonnitrides with metal carbides, titanium nitride, titanium carbonitride, and zirconium oxide. This study examined two different coated cutting inserts to determine which would maximize performance for lathe operators.

The two chemical vapor deposition (CVD) coated indexible inserts examined were Carboloy CMNA 543 TP 100, and Carboloy CNMA 543 TP 10. Both cutting inserts were multi-coated with alumina (Al2O3 ), titanium nitride …

An Investigation Into The Use Of Expanded Polystyrene Patterns With The Loose-Sand, Vacuum Assisted Counter Gravitational Casting Process, John B. Vandersall

Graduate Research Papers

"Considered for years as a metal casting renegade, Expendable Pattern Casting (EPC) is believed by some to be tomorrows long-term casting future. Others, however, see it as an unproven headache-ridden process that makes the simple art of metal casting unnecessarily complex." (Lessiter, 1994, p. 36). The complexity of this process has been largely due to the lack of knowledge surrounding the interaction of the metal front and the dissipating polystyrene pattern.

Since the discovery of EPS as a pattern material, numerous applied research projects have been performed to gain a better understanding of the thermal breakdown characteristics of the material. …

An Analysis Of The Disposition Of Used Foundry Sand With Thermal Reclamation, Douglas Miller

Graduate Research Papers

The purpose of this study was to identify the economic and environmental concerns for the disposal, reuse, or reclamation of used foundry sand and show how foundries have developed options to landfills. The sand type and the reclamation processes available are the factors to use in determining whether disposal, reuse, or reclamation is appropriate. The continued use of landfills for disposal of used sand strongly indicates that reclamation and reuse techniques were either not understood or not as economical as disposal. Public concerns and new environmental laws demand that alternate means of disposal for used foundry sand should be developed …

A Technical Paper On Automated Pouring And The Selection Process Used By One North American Foundry, R. Stanley Weaver

Graduate Research Papers

This report on automated pouring focuses on the selection process used by one North American iron foundry. The problem facing this facility and any operation wishing to implement this technology lies in the number of variables which must be addressed in their quest for a suitable system.

Elasto-Composition Waves In Inhomogeneous Solids, R. C. Batra, Manfred Wuttig

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.