Sure. But, the fatigue and weakening of the metal wouldn't be universal like on the buildings. The buildings had a uniform displacement of loss and strength, any displacement of strength would tend to prove a disaster, ie weak side of building collapses, it didn't.
The "yield strength" of ferrous materials is not a constant but rather varies as a function of ambient temperature. Some steels loose their ductility and become quite brittle below 30 degrees, which is a probable cause in the sinking of the Titanic. They also become more pliable as temperature increases, losing their ability to carry the static load applied at well below the melting point. That characteristic is how a blacksmith can form steel into useful shapes with a hammer without actually melting it and pouring it into a mold.
Stress is the load applied divided by the cross sectional area of the material supporting the load. At the yield point, the material starts to deform which generally decreases the cross section of the supporting member which results in increasing stress while the actual applied load stays constant. The deformation continues until the load bearing member parts, transferring more of the load to the remaining members thereby increasing their stress, &c. &c. until the final supporting members fail nearly simultaneously and the structure collapses.
Nothing that happened to the twin towers on 9-11 requires anything more then a basic understanding of strength of materials to explain. While the airframes were aluminum I doubt that they melted into a convenient pool of liquid metal and found enough water to cause an explosion. It is much more likely that it burned in place. Ockham's razor suggests that the simplest answer is correct.
Regards,
GtG