How to Choose Fasteners for Outdoor & Corrosive Environments
Outdoor fastener selection is not simply a choice between steel and stainless. Rain, humidity, industrial pollution, coastal chlorides, cleaning chemicals, crevices, trapped water and dissimilar metals can all change the corrosion risk of a joint.
Stainless Steel Fastener Corrosion Guide: Pitting, Crevice & Galvanic Risks
Stainless fasteners resist corrosion because chromium in the alloy forms a passive surface film, but that does not mean every stainless screw, bolt or nut is immune to attack..