Joining Aluminium Alloy 5A06 to Stainless Steel 321 by Vaporizing Foil Actuators Welding with an Interlayer

Abstract

Direct aluminium–stainless steel joints are difficult to create by the vaporized foil actuator welding (VFAW) method because brittle intermetallic compounds (IMCs) tend to form along the interface. The use of an interlayer as a transition layer between the two materials with vast difference in hardness and ductility was proposed as a solution to reduce the formation of the IMCs. In this work, VFAW was used to successfully weld sheet aluminium alloy 5A06 to stainless steel 321 with a 3003 aluminium alloy interlayer. Input energy levels of 6 kJ, 8 kJ, 10 kJ, and 12 kJ were used and as a trend, higher energy inputs resulted in higher impact velocities, larger weld area, and better mechanical properties. In lap-shear and peel testing, all samples failed at the interface of the interlayer and target. At 10 kJ energy input, flyer velocities up to 935 m/s, lap-shear peak load of 44 kN, and peel load of 2.15 kN were achieved. Microstructure characterization and element distribution were performed, and the results show a wavy pattern created between the flyer and interlayer which have similar properties, and the interface between the interlayer and target was dominated by element diffusion and IMCs identified mainly as FeAl3 and FeAl. The results demonstrate VFAW is a suitable joining method for dissimilar metals such as aluminium alloy and stainless steel, which has a broad and significant application prospect in aerospace and chemical industry.

A Review on Welding of Dissimilar Metals in Car Body Manufacturing

“…Fig. 4 shows the schematic diagram of the four Nguyen et al 40) Shah et al 41) Zhang et al 63) Wang et al 70) Liu et al 71) Tungsten inert gas (TIG) welding Borrisutthekul et al 42) Song et al 43) Liu et al 64) Wang et al 72) Resistance spot welding (RSW) Pouranvari et al 44) Qui et al 45) Satonaka et al 46) Winnicki et al 47) Baskoro et al 48) Su et al 49) Ibrahim et al 50) Oikawa et al 51) Sun et al 52) Zhang et al 65) Sun et al 66) Min et al 73) Feng et al 74) Laser welding Torkamany et al 53) Dharmendra et al 54) Chang et al 67) Liu et al 64) Li et al 75) Cold metal transfer (CMT) Jácome et al 55) Kang et al 56) Shang et al 68) Ren et al 76) Friction stir welding (FSW) Watanabe et al 57) Morishige et al 69) Chang et al 67) Czerwinski et al 77) Element welding Meschut et al 58) Qui et al 59) Ling et al 60) Ling et al 61) Meschut et al 58) Absar et al 62) Manladan et al 78) Manladan et al 79)…”

Impact Welding of Materials

“…Using a different welding process from the previous works, i.e., vaporising foil actuator welding, Su et al [7] produced aluminium/stainless steel joints with an aluminium interlayer. The authors tested different input energy values and reported that higher energy values promoted welds with higher tensile and shear strengths because of the larger weld areas obtained under these conditions.…”

Behaviour of aluminium/steel hybrid RSW joints under high cycle fatigue loading

“…In recent years special process variants appeared to improve the joint properties, like resistance element welding [15], metallic bump assisted RSW [16], high power ultrasonic welding [17], ultrasonic and resistance spot welding combination [18]. Vaporizing Foil Actuators Welding is also investigated as a solution for aluminium/steel joining [19]. Table 1 contain a summary about special joining processes used in case of aluminium/steel joining, it shows the material grades and additional materials too.…”