Strength of MIG welded connections in fire exposed aluminium structures

Aluminium alloy structures are sensitive to fire exposure, which is mainly due to the low melting temperature. Yet a complete knowledge of the structural behaviour of aluminium alloys when exposed to fire is not available. This paper focuses on one of the main knowledge gaps, being the strength of aluminium welded connections in fire. Uniaxial tensile tests were carried out at elevated temperatures on welded and unwelded aluminium samples of alloys 5083-H111, 6060-T66 and 6082-T6. All welded samples failed outside the weld itself. It is concluded that the difference in strength between the heat affected zone and the parent metal decreases with increasing temperature.