A simplified design of clamping system and fixtures for friction stir welding of aluminium alloys

Abstract

Sound friction stir welds could be attained by using an active design of backing/clamping system with a proper selection of the welding parameters. This work presented a simplified design of fixtures and backing plates to be used for friction stir welding of aluminum alloys. The test-rig was constructed to prevent dispersal or lifting of the specimens throughout the joining process and to ensure uniform distribution of temperature along the plates. The workpieces were subjected to uniform lateral and vertical pressures by means of bolts and nuts. Compound backing plates and pressure bars with additional side plates were included to increase the heat sink. Several coupons of dissimilar aluminum alloys AA7075 and AA6061 were joined to inspect the validity of this design. The tests showed promising results with defects-free welds, good strength and smooth surface finish without geometric imperfection and gap creation between the welded specimens. Efficiency of the joint reached its maximum value of about 82% with respect to the ultimate strength of the AA6061 alloy at 1100 rpm rotation speed and 300 mm/min feed. These results encourage using and improving the present design for future studies of friction stir welding.

An appraisal of characteristic mechanical properties and microstructure of friction stir welding for Aluminium 6061 alloy – Silicon Carbide (SiCp) metal matrix composite

“…Using the specially constructed fixture as shown in Figure 2 to clamp the welding plates, the welding studies were carried out on an automated vertical milling machine. The most important element in FSW to prevent the lifting of the plates to be welded during the welding phase and to verify coherent temperature distribution across the sample plates is the appropriate fixture design with backing plates [18]. The welding variables were adapted to generate defect-free welds based on visual inspection.…”

Friction stir welding of similar and dissimilar aluminium alloys for automotive applications

“…Each zone experiences dissimilar plastic deformations, leading to different shapes of microstructure. In order to produce a sound welding joint, welding parameters such as rotational speed, transverse speed, and position of the metals either on the advancing or retreating side should be considered during the FSW process [13][14][15]. Research by Dawood et al [16] found that reduction in surface roughness reduces friction and narrows down the HAZ at the welding joint.…”

Investigation on TIG welding parameters of 2205 duplex stainless steel

“…Arc welding is a type of welding that uses a welding power supply to create an electric arc between an electrode and the base material to melt the metals at the welding point. Gas tungsten arc welding is also called as TIG welding [6][7][8][9]. Tungsten inert gas (TIG) welding is an arc welding process that produces coalescence of metals by heating them with an arc between a non-consumable electrode and the base metal.…”