Investigation of Microstructure and Mechanical Properties of Welded Joints of Aluminum Alloys Welded with Titanium Based Powder Material by High Velocity Oxygen Fuel Spray Method (HVOF) Combined with Friction Stir Welding Method

Abstract

In this study, spectral analyzes were performed to determine the chemical composition of the samples at 2x40x40 mm taken from aluminum alloy sheet materials. Plates to be combined with friction stir welding were mechanically cut with guillotine scissors at 2x100x300mm. The welded joints of the aluminum plates to be friction-mixed are coated with titanium-based powder material with a thickness of 40µm by high velocity oxygen fuel spraying (HVOF) method. A friction stir tool with a cone tip geometry with machining, 20mm shoulder diameter and 1.8mm pin height was produced for use in the friction stir welding process. In addition, the aluminum alloy sheets prepared were machined according to ASTM E8M-04 standard with dimensions of 2x100x300mm so that they could be joined with friction stir welding on the milling bench. Waterjet drawing and metallographic samples were cut from welded aluminum plates formed with parameters of 2000 rpm rotation speed and 140 mm / min welding speed and 2 degree head angle in accordance with ASTM E8M-04 standard. Tensile specimens were measured on the universal drafting table at a pulling speed of 2 mm / min along with the maximum tensile breaking values ??as well as percent elongation. In order to determine the microstructure and mechanical properties of the weld inserts, hot stamping of the samples, which were not affected by heat, was followed by coarse and fine sanding followed by final polishing with 1µm diamond paste. The hardness values of the samples were determined by Vickers hardness measurement along an axis to characterize the welded zone upper, middle and lower zones to cover all weld zones and the main material.