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Spot friction welding shows advantages over resistance spot welding for joining light alloys for automotive applications. In this research, fatigue behaviors of spot friction welded joints in lap shear specimens of AM-60 magnesium alloy and AA 5754 aluminum alloy were investigated. Static and fatigue tests were conducted with Mg-Mg, Al-Al and Al-Mg specimens. Fatigue S-N curves were obtained for all these specimens using load-controlled fatigue tests. Finite element analysis was conducted to investigate the stress distribution and the location of maximum stresses in spot friction welded joints in Mg-Mg specimens.

Spot friction welding is considered a cost-effective method for joining lightweight automotive alloys, such as magnesium and aluminum alloys. An experimental study was conducted to investigate the strength of spot friction welded joints of magnesium to magnesium, aluminum to aluminum, magnesium to aluminum and aluminum to magnesium. The joint structures and failure modes were also studied.

The effects of lubricant on lap shear strength of Spot Friction Welded (SFW) joints made of 6111-T4 alloys were studied. Taguchi L8 design of experiment methodology was used to determine the lubricant effects. The results showed that the lap shear strength increased by 9.9% when the lubricant was present at the top surface compared to that of the baseline (no lubricant) whereas the lap shear strength reduced by 10.2% and 10.9% when the lubricant was present in the middle and at the bottom surfaces compared to that of the baseline (no lubricant), respectively. The microstructure analysis showed a zigzag interface at the joint between the upper and the lower sheet metal for the baseline specimen, the specimens with the lubricant at the top and at the bottom. However, a straight line interface is exhibited at the joint between the upper and the lower sheet for the specimen with the lubricant in the middle. The weld nugget sizes of the lap shear tested specimens were measured.

This paper presents a comparison of aqueous corrosion rates in 5% NaCl solution for eight experimental creep-resistant magnesium alloys considered for automotive powertrain applications, as well as three reference alloys (pure magnesium, AM50B and AZ91D). The corrosion rates were measured using the techniques of titration, weight loss, hydrogen evolution, and DC polarization. The corrosion rates measured by these techniques are compared with each other as well as with those obtained with salt-spray testing using ASTM B117. The advantages and disadvantages of the various corrosion measurement techniques are discussed.

This paper describes the results of dynamic denting experiments conducted on AA5754 and AA6061 alloys. Dynamic denting tests were performed using a drop weight impact machine. The drop height was varied from 38 mm to 914 mm to generate impact velocities ranging from 53.4 m/min to 254 m/min. The dent depth created at different drop heights was related to the input impact energy and peak load observed in the tests. The effects of sheet thickness and yield strength were explored.

This paper describes an experimental work on the bending springback of aluminum alloy 5754. Experiments were performed using a 90° V-shaped matching die-punch combination, with and without clamping. Clamping was used to create tension during bending. The experimental parameters taken into account are the die radius, sheet clamping torque, sheet thickness and the level of cold work in the sheet.

This paper presents the static and fatigue strength evaluation of clinched joints in 6111-T4 aluminum alloy sheets. Clinched joints are mechanical joints produced a cold forming technique using a small die-punch combination. A design of experiments approach is used to determine the optimum die-punch combination that produces the least variation in the static pull-out load in single lap shear tests. Fatigue S-N curves are determined for several different clinched joints in load-controlled fatigue tests with the load ratio equal to 0.1. The effect of heat exposure, typically experienced in paint ovens, on the static strength as well as fatigue S-N behavior are also examined.