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In the present study, the effect of an La alloying element with different quantities (1, 3 and 5 wt.-%) on the microstructure, mechanical and dry sliding wear properties of Mg- 3Al-3Sn-3Sb alloy was investigated. The wear tests were done on the alloys using pin on-disk equipment against a 4140 steel disc as counterpart under three different sliding velocities of 0.3, 0.6 and 1.2 ms-1 and four different loads of 5, 10, 20 and 40 N. The microstructural results showed that the new intermetallic phases (La5Sn3 and LaSnSb2) were formed with addition of La to the main alloy. Also, it was observed that the hardness of the Mg-3Al-3Sn-3Sb alloy was raised with increasing La addition. Furthermore, the tensile properties of the Mg-3Al-3Sn-3Sb alloy improved with rising La content at room and elevated temperature. The wear rates of the alloys increase with increasing of the sliding speed and load. In addition to this, the wear rate of the Mg-3Al-3Sn-3Sb alloy was found to be higher than that of the La content alloys for all test conditions.

WOS: 000373167400006, In the Van Earthquake of magnitude Mw = 7.2 on October 23, 2011, 48,666 buildings were severely damaged or collapsed, 604 people lost their lives and 1301 people were injured. During this earthquake, not only the buildings designed in accordance with the old earthquake codes but also the ones designed in accordance with the current Turkish Earthquake Code (TEC) were severely damaged. The purpose of this study is to reveal the reasons why the RC buildings designed in accordance with the current TEC as a result of static and dynamic calculations were severely damaged in the recent earthquakes. In this study, first, the buildings that were designed in accordance with the last two earthquake codes and damaged during the Van Earthquake on 23 October 2011 have been examined. Then, another severely damaged building that was designed in accordance with the TEC 2007 has been chosen as a possible model for similar situations. In order to explore the reasons behind the damage, detailed examination has been made both in the damaged structure and in its design calculations. Both situations in the project and implementation of the design have been analyzed by using IdeCAD and Sta4CAD modeling, as well as Sap2000 through which weak structural members have been determined. The findings have been evaluated in terms of design and implementation flaws, in compliance with the TEC 2007, modeling and acceptance error. When analyzed by modeling of its project, the building has not revealed any insufficient columns; however, in its implementation analysis, the damaged members have appeared to be insufficient. It has been determined that the damage was due to improper implementation of the project, incompatible production according to the TEC 2007 and lack of inspection. To mitigate possible fatalities and damages in the future earthquakes, implementations should be fully represented in the model of the projects, structural members in the projects should be built identically to their design, attention should be paid to the anticipated limitations in TEC 2007 during implementation, and stages of project and implementation should be inspected sufficiently. (C) 2016 Elsevier Ltd. All rights reserved., Mustafa Kemal University, The studies performed in the region after the Van Earthquake have been carried out by M. Cemal Genes from Zirve University, Hakan T. Turker and Selcuk Kacin from Mustafa Kemal University along with Mustafa Kemal University Civil Engineering students Muhammet Sadik Lenk, Bekir Danyildiz, Aytac Guler and Ilker Basaran with the sponsorship of Mustafa Kemal University. Hatay Chamber of Civil Engineers has provided logistic support contacting the Van branch. Civil Engineers Ilhan Gunay and Ferman Toro, who work in Van and Ercis, have supported on-site examinations in the area. Civil Engineers Muzeyyen Balcikanli and Bunyamin Akyol have also helped with the study. Sap2000, IdeCAD and Sta4CAD softwares have given support regarding the licenses. The authors express their sincere thanks to the above-mentioned people, institutions and organizations for the support they have provided.

WOS: 000372851000015, This paper describes the fatigue failure of a rotary dryer in a chemical plant. The process conditions required the dryer to be rotated continuously at a speed of about two and half revolutions per minute. The shell structure of this large drum is formed by combining segmented shell parts using bolted ring flange joints. Because of the gross weight of the dryer in operation time, each joint was subjected to bending moment. In the first two years in service, micro cracks were occurred by fatigue. The failure was analyzed using the fatigue curves given in ASME Boiler and Pressure Vessel Code Section VIII Division 2 and EN 13445 Unfired Pressure Vessels Part 3 Codes. Finally, flange joints were removed from the drum and new cylindrical parts adapted to the drum using butt welding after reaching better results in FEM and fatigue calculation. (C) 2016 Elsevier Ltd. All rights reserved.

WOS: 000381839900017, This paper describes the fatigue failure of girth gear manufactured from low alloy cast steel of rotary dryer in a chemical plant. The cracks of T-section web of the girth gear occurred at the end of 25 year working period because of stress intensity factor. Because of normal condition of working surfaces of teeth, spare gear was not thought and repair welding was the only option. Nickel based super alloy electrode was used for repairing and it had been successful until the new gear was ordered. The factors behind the fatigue failure and the reasons of temporary repairment were discussed using the cause-effect diagram. Higher grade bolt using instead of design grade, insufficient stiffener of web, insufficient preparation of repair welding and wide section welding beads at the welding deposits were found as the reasons of changing the girth, gear with the new one. (C) 2016 Elsevier Ltd. All rights reserved.