The expert panel investigating the accident believed this to be the first fatal aircraft accident anywhere in the world directly attributable to metal fatigue.
Thus, delamination is an insidious kind of failure as it develops inside of the material, without being obvious on the surface, much like metal fatigue.
Bronze resists corrosion (especially seawater corrosion) and metal fatigue more than steel and is a better conductor of heat and electricity than most steels.