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Impact of TIG Welding Parameters on the Mechanical Properties of 6061-T6 Aluminum Alloy Joints

Kareem Salah Sabeeh Abed Al, Mahdi Basma Luay, Hussein Hiba K.

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 5

114--129

EN

The most common gas-shielded arc welding method is tungsten inert gas welding, which uses shielding gas to isolate the welded area. Such technique is mostly used in the industrial domain, including steel framework fabrication and installation, plumbing systems, and other building jobs. The welding method and the implementation of a suitable welding joint based on some factors that contribute to the fusion process were studied in the present research. The research investigated the specifications and efficiency of the area to be welded in terms of the thermal effect on the welding joint shape and some significant mechanical property-related factors which that were determined during the welding process. In this paper, aluminum alloy sheets, AA 6061-T6, with a thickness of 3 mm, were used with a 60mm width and 80mm length. These sheets were prepared to be welded using welding currents of 90A, 95A, and 100A, welding speeds of 60mm/min, 80 mm/min, and100 mm/min, and gas flow rates of 8 l/min, 9 l/min, and 10 l/min. The experiments were designed at three distinct levels. These levels were selected to create the L9 orthogonal array. Regression analysis, signal-to-noise ratio evaluation, and analysis of variance were carried out. The created model has enhanced accuracy by predicting the reinforced hardness found in the weld specimens, according to the regression study, which showed R2= 90.09%. In addition, it was discovered that the ideal welding parameters for a welded specimen were 100 A for welding current, 80 mm/min for welding speed, and 9 l/min for gas flow. The present research examined the shape of the thermal distribution of welded parts using the engineering computer program ANSYS. The experimental results clarified the proposed approach, as they showed that the welding current is the most influential factor in the hardness of the weld using the fusion process of 90.95%, followed by the welding speed of 7.48%, while the gas flow rate of 1.52% has the least effect. The authors recommend using qualified welders to ensure optimal performance. It is anticipated that these findings will serve as a foundation for analysis to optimize welding processes and reduce welding defects.

2

Application of the Ansys Fluent program for modelling environmental phenomena in a living room

Kosiń Mariusz

Budownictwo o Zoptymalizowanym Potencjale Energetycznym

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2021

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Vol. 10 Nr 2

53--59

EN

The article presents a three-dimensional numerical analysis of heat and humidity parameters carried out for a living room in a multi-family building. The aim of the analysis was to compare alternative heating methods with the existing one. Two cases were included in the analysis: case I - the existing state, case II - the existing state with an additional panel heater. In order to verify the numerical analysis for case I, the temperature and relative humidity were measured. During the heating period, the thermal conditions in the room did not favor the comfort of users, especially in one part of the room. The study may be a tool for future research related to the implementation of the climatic conditions of rooms with similar structural and functional features.

3

Heatsink design using iterative calculation and thermal simulation for three-phase inverter

Resutik Patrik, Kascak Slavomir

Przegląd Elektrotechniczny

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2020

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R. 96, nr 12

63--66

EN

The design of the power electronics system requires a crucial step – power loss estimation. When losses are estimated by the simulation approach it can significantly reduce the design time of the device cooling solution. This paper presents an estimation of power losses in three phaseinverter in different operation points, to determine the worst-case scenario. For this simulation, MATLAB Simulink is used, and simulation results in the form of the losses are used in another software to visualize thermal spreading at the heatsink.

PL

W projektowaniu urządzeń energoelektronicznych dużą rolę odgrywa ocena strat mocy skutkujących wydzielaniem ciepła. Artykuł prezentuje ocenę strat mocy w trójfazowym przekształtniku. Określono rozpraszanie się ciepła w tym urządzeniu.

4

Analysis of non-equidistant baffle spacing in a small shell and tube heat exchanger

Aziz Abdullah, Rehman Shafique

Archives of Thermodynamics

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2020

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Vol. 41, no 2

201--221

EN

Most of the formulations regarding the characteristics of a shell and tube heat exchanger have a common assumption; namely that the baffle plates are equidistant. This assumption fails to cater the real world scenario for defective baffles as the alteration in a shell and tube heat exchanger invalidates the equidistant baffle spacing of the plates. In this regard, a small six baffles heat exchanger was modeled in the computational fluid dynamics software package and studied by removing each baffle plate one at a time. Effect of removing each baffle plate on the temperature, pressure, heat transfer coefficient, and total heat transfer rate was recorded. It was observed that variation in the pressure drop for the same number of baffle plates varies along the axial order of the plates. The change in pressure drop due to the removal of the baffle plate near the inlet and the outlet was lowest and reaches a maximum in the axial center. It was also found that the plates below the radial center contribute higher towards the overall heat transfer as compared to those above.

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The use of thermal mapping in evaluation of mechanically induced electrical degradation of graphene - based transparent heaters

Kozłowska A., Gawlik G., Piątkowska A., Krajewska A., Kaszub W.

Materiały Elektroniczne

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2017

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T. 45, nr 1

12--17

EN

The purpose of this study is to investigate temperature distributions of graphene-based transparent heaters deposited on glass. Furthermore it analyses the influence of layer discontinuities such as scratches and cracks on the performance of Joule-heated samples. Graphene mechanical strength was examined by the nanoscratch method at incremental loads using a ball on a flat sample surface. In the case of the controlled load several scratches were produced on the graphene surface. Tribological tests were conducted at different constant loads. the paper presents scanning electron micrograph (seM) observations of the modified graphene surface. Infrared imaging of Joule-heated samples indicates a significant uniformity deterioration of the thermal maps due to the current flow alteration in the presence of structural imperfections. The results obtained in the course of this study give new insight into the role of defects such as cracks or discontinuities in the overall performance of graphene transparent layers.

PL

W pracy przeprowadzone zostały badania rozkładów termicznych elementów grzejnych zawierających warstwy grafenowe naniesione na szkło. Analizowany był wpływ nieciągłości warstwy w postaci zarysowań i pęknieć. Mechaniczna wytrzymałość grafenu badana była za pomocą metody nano-zarysowań przy narastającym obciążeniu kulki oddziaływującej na płaską powierzchnię próbki. Przy zastosowaniu kontrolowanego maksymalnego obciążenia wykonano szereg rys na powierzchni grafenu. Przeprowadzono testy tribologiczne dla różnych stałych obciążeń. W pracy zawarto wyniki analizy zmodyfikowanej powierzchni grafenu za pomocą skaningowego mikroskopu elektronowego (SEm). Obrazowanie w podczerwieni próbek podgrzewanych za pomocą wydzielanego ciepła Joula wskazały na znaczne pogorszenie jednorodności rozkładów termicznych, na skutek zmiany drogi przepływu prądu w przypadku występowania niedoskonałości strukturalnych. Wyniki pozwalają na ocenę wpływu defektów w postaci pęknięć i nieciągłości na działanie przezroczystych grafenowych warstw grzejnych.

6

Badania nad wykorzystaniem krajowej biomasy w produkcji zasypek odlewniczych

Pogorzałek J., Borecki M., Różański P.

Prace Instytutu Metalurgii Żelaza

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2013

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T. 65, nr 4

8--17

PL

Przedstawiono przebieg i wyniki prac badawczych mających na celu opracowanie technologii wytwarzania zasypek odlewniczych dla stalownictwa z wykorzystaniem krajowej biomasy. Przeprowadzono badania właściwości fizyko-chemicznych wybranych odpadów z przemysłu rolno-spożywczego celem porównania z właściwościami szeroko stosowanej obecnie łuski ryżowej. Wykonano analizy chemiczne, analizy termiczne TG-DSC w atmosferze obojętnej i utleniającej oraz laboratoryjne badania procesu termicznego rozkładu otrąb, plew i innych odpadów z przetwórstwa krajowych zbóż. Skuteczność opracowanych składów zasypek izolacyjnych i izolacyjno-egzotermicznych z wykorzystaniem w/w biomas oraz odpadów mineralnych w postaci żużli stalowniczych określono w warunkach laboratoryjnych. Stwierdzono możliwość zastąpienia importowanej łuski ryżowej krajowymi odpadami przemysłu zbożowego w zasypkach odlewniczych.

EN

The paper presents the course and results of the research works aimed at developing technology for manufacturing casting powders for steelmaking using the domestic biomass. The tests of physical and chemical characteristics of selected waste from the food processing industry were carried out to compare them to those of the rice husk which is widely used at present. Chemical analyses, TG-DSC thermal analyses in inert gas atmosphere and in oxidizing atmosphere conditions and laboratory tests of thermal decomposition of bran, chaffs and other wastes from domestic cereals treatment processes were done. Insulation efficiency of developed casting powders (insulating and exothermicinsulating types) based on the above-mentioned biomasses and mineral wastes (steelmaking slags) was determined in laboratory scale. It was concluded that domestic biomasses (wastes from the food processing industry) could replace the imported rice husk in casting powders.