“…6) Several solid state welding methods have been investigated to join steel and aluminum alloy, including explosion welding, 7,8) ultrasonic welding, 9) magnetic pressure welding, 10,11) friction welding [12][13][14] and friction stir welding. 15,16) The solid state welding techniques are expected to restrain the growth of the intermetallic compound layer within a permissible limit, which has been identified as 10 μm thickness, 17) but the adaptability of these methods is restricted in automotive industry due to equipment configuration. In the last few years, arc welding-brazing, [18][19][20][21] laser reactive wetting 6) and laser brazing 4,5,[22][23][24][25] of the dissimilar materials of steel and aluminum alloy have drawn great attentions.…”