The fasteners in this industry, in addition to having to withstand the aggressive corrosion action of seawater, routinely require high performance in terms of mechanical strength.

It becomes necessary, therefore, to find more technologically advanced solutions than “traditional” stainless steels, both as materials, that is, the recent super alloys, and of coatings of the latest generation.
Duplex/Super-Duplex stainless steels and exotic alloys such as Monel 400 and Monel K500 are widely used. Specific PTFE coatings, in addition to further protection, add the ability to maintain a low coefficient of friction when parts are scheduled to be disassembled for maintenance after some time.