EXPERIMENTAL OBSERVATION OF DIFFERENT WELDING PARAMETERS FRICTION STIR WELDING


Thesis Type: Postgraduate

Institution Of The Thesis: Gazi University, Fen Bilimleri Enstitüsü, Turkey

Approval Date: 2007

Thesis Language: Turkish

Student: Mehmet BOZU

Supervisor: MURAT TOLGA ÖZKAN

Abstract:

Butt welding has been treated to Al 7075 T6 materials through friction stir welding method which is a brand-new way introduced in friction welding. Friction stir welding has been modelled with finite elements method by evaulating the derived conclusions from the works have been done up to present. While welding in progress, such variables as needle form of the stirer tool, butt form of the stirer tool, spindle speed, feed rate and position of the mould; are used as parameters. Temperature values of the welding were measured using thermocouple. Tensile strenght and surface roughness experiments have been conducted to the welding samples. After some experiments it has been observed that, rising feed rate increase tensile strength in welded samples whereas rising spindle speed weakens tensile strength due to the high level heat occurance. Best mechanical properties have been designated by those samples which are welded with 20mm/m feed rate, 900 rpm spindle speed and A-type stirer tool. Moreover, it is observed that increasing feed rate value concludes with lower temperature occurance while higher spindle speeds leads to higher temperature values. Surface rougness experiment concluded in that the higher the feed rate is the lower the surface rougness value. Science Code : 708.1.090 Key Words : Friction Stir Welding