OVERVIEW:
4043 Aluminum Silicon alloy is very commonly used for welding on 6XXX base materials and other heat treatable alloys. 4043 is a soft alloy, with good crack resistance and high penetration compared to other filler metals. It can be used for certain brazing applications and to weld on high silicon casts like A356. Welding of 5XXX with 4043 and other 4XXX filler metals should be avoided.
