IJET Vol. 3, Issue 2, June 2017International Journal of Engineering Technologies (IJET) Dergisi kayıtlarını içerir.https://hdl.handle.net/11363/5322024-03-28T18:25:50Z2024-03-28T18:25:50ZInternational Journal of Engineering Technologies (IJET) Vol. 3, Issue 2, June 2017https://hdl.handle.net/11363/20642020-04-16T18:45:42Z2017-01-01T00:00:00ZInternational Journal of Engineering Technologies (IJET) Vol. 3, Issue 2, June 2017
Bayram, Mustafa
Dear Colleagues,
On behalf of the editorial board of International Journal of Engineering Technologies (IJET), I
would like to share our happiness to publish the tenth issue of IJET. My special thanks are for
members of editorial board, publication board, editorial team, referees, authors and other technical
staff.
Please find the tenth issue of International Journal of Engineering Technologies at
http://ijet.gelisim.edu.tr or http://dergipark.gov.tr/ijet. We invite you to review the Table of
Contents by visiting our web site and review articles and items of interest. IJET will continue to
publish high level scientific research papers in the field of Engineering Technologies as an
international peer-reviewed scientific and academic journal of Istanbul Gelisim University.
Thanks for your continuing interest in our work,
Professor Mustafa BAYRAM
Istanbul Gelisim University
mbayram@gelisim.edu.tr
http://ijet.gelisim.edu.tr
http://dergipark.gov.tr/ijet
Printed ISSN: 2149-0104
e-ISSN: 2149-5262
2017-01-01T00:00:00ZProminence of Hadfield Steel in Mining and Minerals Industries: A ReviewOkechukwu, ChijiokeDahunsi, Olurotimi AkintundeOke, Peter KayodeOladele, Isiaka OluwoleDauda, Mohammedhttps://hdl.handle.net/11363/5382021-08-26T12:33:46Z2017-06-28T00:00:00ZProminence of Hadfield Steel in Mining and Minerals Industries: A Review
Okechukwu, Chijioke; Dahunsi, Olurotimi Akintunde; Oke, Peter Kayode; Oladele, Isiaka Oluwole; Dauda, Mohammed
High manganese austenitic steel, popularly called “Hadfield steel” has dominated and played significant role in wear applications, especially in the mines and minerals industries since its invention over a century ago. A review on the researches on this steel revealed that its prominence in these fields is mainly due to its good combination of impact and abrasion wear resistance arising from its high toughness and high hardness respectively. Its strain hardening ability under impact loading is evidenced by increase in hardness as the material work hardens; this lowers the amount of wear in service. The work hardening property of the steel has been linked to governing mechanisms such as dislocation, deformation twinning, and dynamic strain ageing; also, it is enhanced by increase in carbon, ageing temperature and reduction in manganese content. Carbide precipitation along the grain boundaries and within the grains is the major cause of embrittlement of the steel. These carbides together with voids and porosities during casting solidification, improper heat treatment, overheating during welding, use of unsorted scrap metal and wrong wear application have been identified as the causes of premature failure in service. Hardfacing method has been proposed as a means of substituting the steel in wear applications, as alternative wear materials such as white cast iron and austempered ductile iron lack the combination of impact and abrasion resistance being offered by the Hadfield steel.
DOI: 10.19072/ijet.299068
2017-06-28T00:00:00ZOptimum Insulation Thickness for the Exterior Walls of Buildings in Turkey Based on Different Materials, Energy Sources and Climate RegionsAktemur, CenkerAtikol, Uğurhttps://hdl.handle.net/11363/5372021-08-26T12:33:46Z2017-06-28T00:00:00ZOptimum Insulation Thickness for the Exterior Walls of Buildings in Turkey Based on Different Materials, Energy Sources and Climate Regions
Aktemur, Cenker; Atikol, Uğur
Thermal insulation improves the strength and longevity of buildings by reducing energy consumption, and as a related result, improved energy use. The selection of insulation material is governed by important parameters, including the average outdoor air temperature, the thermal conductivity of the buildings and the cost of the insulation material. Increases in the thickness of the insulation material will gradually decrease the energy consumption for heating; however, the insulation thickness has an optimum value that minimises the total investment cost, and determination of this optimum value is critical for economic analysis. In this paper, a life-cycle cost analysis is presented to show the optimum insulation thickness, energy savings over a lifetime of 15 years and payback periods for six different fuels and insulation materials for four cities in Turkey selected from climate regions identified by the Turkish Thermal Insulation Standard (TS 825). Muğla (1st region), Kocaeli (2nd region), Ankara (3rd region) and Ardahan (4th region) were selected for analysis of a sandwich-type wall constructed from the following six insulation materials: extruded polystyrene, expanded polystyrene, glass wool, rock wool, polyisocyanurate and polyurethane. The calculations were also made on the basis of six different fuels, such as motorin, natural gas, propane (LPG), electricity, coal (imported), and fuel-oil No. 4. As a consequence, results demonstated that the optimum insulation thickness vary between 2.8 cm and 45.1 cm, with energy savings between 16.4 ₺/m2 and 479 ₺/m2, and payback periods fluctuating between 0.078 and 0.860 years, depending on the city, the insulation material, and the cost of fuel.
DOI: 10.19072/ijet.307239
2017-06-28T00:00:00ZConceptual Guideway Structural Design for MAGLEV High-Speed Ground Transportation SystemBalkaya, CanHall, W.J.https://hdl.handle.net/11363/5362021-08-26T12:33:46Z2017-06-28T00:00:00ZConceptual Guideway Structural Design for MAGLEV High-Speed Ground Transportation System
Balkaya, Can; Hall, W.J.
The conceptual guideway structural designs for MAGLEV (magnetic-levitation) high-speed ground transportation system are discussed by considering four different guideway designs of Bechtel, Magneplane, Grumman and Foster-Miller. The important aspects of the conceptual designs as well as some of the apparent shortcomings that will need attention in the design studies are emphasized. In this context the technical assessments and design observations may be considered for the guideway conceptual designs are given in this study.
DOI: 10.19072/ijet.309372
2017-06-28T00:00:00Z