BARLAS, Zafer Sakarya Üniversitesi, Esentepe Kampusu - Teknik Eğitim Fakültesi, Turkey , UZUN, Hüseyin Sakarya Üniversitesi, Esentepe Kampusu - Teknik Eğitim Fakültesi, Turkey

INVESTIGATION OF MICROSTUCTURAL AND MECHANICAL PROPERTIES OF FRICTION STIR WELDED Cu/Al-1050 BUTT JOINT

16417

In this study, the weldability of pure copper (Cu) plate to aluminum (Al-1050) plate has been nvestigated at a constant tool rotation speed of 515 rpm and different weld speeds by friction stir welding. While a relatively sound Cu/Al-1050 joint was achieved at the lowest weld speed (12 mm min^-1), very poor joints were obtained at the higher weld speeds (30 and 50 mm min^-1). Therefore in this study, microstructural characterization and mechanical properties of the joint at weld speed of 12 mm min^-1 were evaluated. Microstructure investigations by optical microscope and scanning electron microscope, energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), tensile test and microhardness measurements were carried out in this joint. Microstructure inspections and EDS analysis revealed that the stir zone of the joint consisted of aluminum-rich and copper-rich structures. AlCu, Al2Cu3, AlCu4 and Al4Cu9 intermetallic compounds were detected in the weld region by XRD. Volume fraction of copper-rich phases in the stir zone was calculated by image analysis software which is approximately 32%. Tensile test results show that the tensile strength of Cu/Al-1050 joint lower 50% and 24% than that of Cu base metal and Al-1050 base metal, respectively. It was observed that hardness’s in the stir zone increased when compared to the base metals and varied between 74 HV and 280 HV.

857

Friction stir welding , Cu , Al , 1050 butt joint , microstructural characterization , mechanical properties

Journal Of The Faculty Of Engineering an‎d Architecture Of Gazi University

865