Laser and TIG welding of additive manufactured Ti-6Al-4V parts

Abstract

Electron beam melting (EBM) is a powder bed additive manufacturing (AM) technology for small and medium-sized Ti-6Al-4V components. In this study, EBM-built Ti-6Al-4V tensile specimens were joined using tungsten inert gas (TIG) welding and laser beam welding (LBW) to form large-scale components. Weld morphology, defects, mechanical properties, and microstructure of joints made by LBW and TIG welding were compared. It was found that the pore sensitivity of EBMed Ti-6Al-4V is extremely high. In EBM, the most common defect is pores, but this has been ignored as parts are broken at welding zone. Large pores are distributed along the edge of the weld in TIG welding, whereas in laser welding they are distributed at top of the weld. LBW has a much smaller grain size in the weld center than TIG welding. The TIG welded sample has more heat at the weld boundary. Mechanical properties of TIG welded parts were superior to laser welded parts. The main reason for this is that the weld cross section is larger than the center. In addition, in the microstructure examination of TIG welding, it was observed that the weld had fewer defects than laser welding. Also, the elongation of all specimens is very low.

Micro drilling characterization of the carbon and carbon–aramid (hybrid) composites

“…Composites are widely used in aerospace, 1 automotive, 2 and industrial applications due to their high strengthto-weight ratio and excellent mechanical properties along with titanium. [3][4][5][6] Currently, micro-drilling of composites finds extensive application in various fields, including aircraft engine nacelle, and wind turbine blades in order to reduce noise which results in acoustic fatigue damage. [7][8][9] Mechanical drilling and laser drilling methods are common practices for fiber-reinforced composites and in some cases, combining these techniques allows for optimizing efficiency, balancing cost considerations with the need for precision in composite hole-making processes.…”

“…Composites are widely used in aerospace, 1 automotive, 2 and industrial applications due to their high strength‐to‐weight ratio and excellent mechanical properties along with titanium 3–6 . Currently, micro‐drilling of composites finds extensive application in various fields, including aircraft engine nacelle, and wind turbine blades in order to reduce noise which results in acoustic fatigue damage 7–9 .…”

The Engine Casing Machining Holes Repairing Based on Vibration Wire Feeding

“…This resulted in greater tensile strength and hardness compared to low heat input. The weld seam morphology, defects, mechanical properties, and microstructure of deposits obtained by Electron Beam Melting (EBM), Tungsten Inert Gas (TIG), and Laser Beam Welding (LBW) of Ti-6Al-4V were compared [23,24]. The results revealed that internal defects in EBM Ti-6Al-4V samples produced during the manufacturing process were smaller than those occurring during the welding process.…”