4. Corrosion Resistance The black phosphate coating not only provides a sleek finish but also protects the screws from rust and corrosion. This is crucial in regions with high humidity or in applications where moisture may be a concern, ensuring that the integrity of the assembly remains intact over time.

The functionality of metal expansion nuts centers around the principle of mechanical expansion. Upon the application of torque, the screw or bolt is threaded into the nut, which, in turn, causes the nut to expand outward. This outward expansion presses the sides of the nut against the inner walls of the hole it occupies, creating a tight fit. The added friction and mechanical grip prevent the nut from loosening over time, even in dynamic conditions.

2. Enhanced Durability The galvanized coating provides excellent protection against rust and corrosion, ensuring that the screws maintain their integrity even in harsh environments. This durability is crucial for projects exposed to the elements or in industries where equipment is subjected to moisture, chemicals, and other corrosive substances.