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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Cleavage initiation in the intercritically reheated coarse grained heat affected zone of steels

Davis, Claire Louise January 1994 (has links)
No description available.
192

Sensor based automatic control system for narrow gap TIG welding

Chen, Xiao-Qi January 1989 (has links)
No description available.
193

Ultrasonic surface waves seam tracking and penetration control in thin materials

Egharevba, F. E. January 1988 (has links)
No description available.
194

Evaluation of hot gas welding techniques for the joining and repair of polymeric bumper materials

Turner, Brian Edward January 1990 (has links)
No description available.
195

Generation of welding procedures for the submerged arc process using expert system techniques

Taylor, W. A. January 1987 (has links)
No description available.
196

Fusion welding of crosslinked polyethylene

Ovington, Stephen January 1995 (has links)
No description available.
197

Modeling of thermal and mechanical effects during friction stir processing of nickel-aluminum bronze

Jamison, Jay Dee 09 1900 (has links)
Approved for Public Release; Distribution is Unlimited / Friction Stir Processing (FSP), although relatively simple in concept, results in an extremely complex thermomechanical treatment to the material being processed. Previous studies of FSP have shown that the process results in extremely high strain, strain rates and temperatures as well as gradients in strain, strain rate and temperature within a small volume of material. This thesis will study the effect of varying FSP parameters during the processing of Nickel-Aluminum-Bronze (NAB) propeller material. The modeling program CTH was used to define the relationship between tool rotation speed, traversing speed and the total power input to the material. The tool's mechanical power and the power generated by deformation of the material has been investigated. The modeling experiments were designed to gain an understanding of the relationship of process parameters, microstructure and mechanical properties, and to enhance our understanding of the flow patterns and thermal histories of the NAB material in the stir zone. / Lieutenant, United States Navy
198

Resistance spot welding equipment controller - Beijer iX T7B Softmotion based weld equipment controller

Hermansson, Olaf January 2016 (has links)
The goal of the project is to evaluate a new setup for the company Iberobot Svenska AB, using HMI and PLC, for resistance spot welding equipment controller. The purpose of the controller is to control the weld process; weld power and time. One of the question raised is if this setup could be used as an RWE controller and thereby be able to re-place an old proprietary controller called TEC6000. A prototype is built compatible with current single phase RWE and literature study is conducted to answer this question.  The new setup is based on Beijer iX T7B Softmotion which includes an HMI and a PLC with EtherCAT support. EtherCAT input and output modules from Beckhoff are chosen because they can handle the speed required by the weld process. The controller is implemented using theory for RMS value, timing diagram and state diagram based on weld process. The prototype is revised three times. A zero crossing detector is implemented. A control element driver using opto-triac is implemented. Measurements using oscillo-scope are conducted which shows that the controller is able to start a weld, but zero crossing detection is unstable and further research into this and current regulation is needed before an end user product can be made.
199

Modification of the exhaust system in the welding lab of Durland Hall at Kansas State University

K̲h̲ān̲, Arshad ʹAlī January 2010 (has links)
Typescript, etc. / Digitized by Kansas Correctional Industries
200

Influência da potência de laser Nd: YAG na soldagem do aço inoxidável duplex UNS S32205 /

Crespo, Gillian da Silva. January 2014 (has links)
Orientador: Vicente Afonso Ventrella / Co-orientador: Ruís Camargo Tokimatsu / Banca: Wyser José Yamakami / Banca: Angelo Caporalli Filho / Resumo: Conduziu-se um estudo da soldagem laser na condição "bead on plate" no aço inoxidável duplex UNS S 32205 na forma de chapas com 3,0 x 20 x 45 mm (A x L x P). Realizou-se 12 soldas em atmosfera de gás argônio com fluxo de gás de 15 l/min, diâmetro de feixe de 0,2 mm, ângulo de 90º, taxa de repetição de 9 Hz, velocidade de soldagem de 150 mm/min, profundidades de foco iguais a 1,0; 1,5 e 2,0 mm abaixo da superfície da peça e energia do pulso (Ep) fixada em 6,0 J. A variação de potência foi obtida variando as larguras temporais (Lt) em valores de 4, 6, 8 e 10 ms. Os resultados foram analisados com base na relação entre potência, geometria do cordão de solda, balanço de fases ferrita/austenita, dureza Vickers e análise química. Para revelação dos metais de solda utilizou-se reagentes Behara modificado e eletrolítico com solução oxálica 10%. As medidas de geometria (largura e profundidade) dos cordões de solda foram realizadas através de imagens obtidas através de câmera digital em um microscópio óptico comum. O processamento das imagens foi realizado através do programa "Image J", um software de edição de imagens de domínio público pautado na plataforma Java. Os maiores valores de largura e profundidade foram encontrados nos maiores valores de potência e o aumento do valor da posição focal acarretou em um aumento da variabilidade da média desses parâmetros geométricos. O valor do balanço ferrita/austenita para o metal base e metal de solda foi de 52/48 % e 70/30 % respectivamente. O valor médio da dureza para o metal base foi igual a 286 HV. Nos metais de solda e nas ZTAs a posição focal -1,5 mm apresentou os menores valores de dureza, independente da potência utilizada. A composição química dos elementos de liga não apresentou grandes variações entre os dados de fábrica e os obtidos para o metal base e o metal de solda / Abstract: We carried out a study of laser welding provided "bead on plate" in duplex stainless steel UNS S 32205 in the form of plates with 3,0 x 20 x 45 mm (H x W x D). 12 welds was performed in argon gas flow of 15 l/min, beam diameter 0,2 mm, angle of 90°, repetition rate of 9 Hz, welding speed of 150 mm / min, gas depths focus equal to 1,0; 1,5 and 2,0 mm below the surface of the workpiece and the pulse energy (Ep) set at 6,0 J. The power variation was obtained by varying the time width (Lt) at values of 4, 6, 8 and 10 ms. The results were analyzed based on the relationship between power, weld bead geometry, balance ferrite/austenite phases, Vickers hardness and chemical analysis. For structure revelation of the weld metals used both Behara modified and electrolyte with 10% oxalic solution reagents. Measures of geometry (width and depth) of the weld beads were made using images taken by digital camera on an ordinary optical microscope. Image processing was performed using the "Image J" program, a graphics editing software in the public domain lined on Java platform. The highest values of width and depth were found in higher values of power and increasing the value of the focal position resulted in an increase in the variability of the mean of these geometrical parameters. The balance sheet value of the ferrite/austenite for the base metal and weld metal was 52/48 % and 70/30% respectively. The average hardness for the base metal was equal to 286 HV. In weld metals and the ZTAs focal position -1.5 mm had the lowest hardness values, regardless of power used. The chemical composition of alloying elements did not show large variations between factory data and those obtained for the base metal and the weld metal / Mestre

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