Choosing Fastener Materials and Finishes

Fastener material and finish should be selected together with strength, environment, mating parts and installation method. A stronger grade is not automatically the best choice if corrosion, hydrogen embrittlement or galvanic compatibility is overlooked.

Questions to confirm

Is the assembly indoors, outdoors, coastal or exposed to chemicals? What temperature and design life are expected? Is coating thickness restricted by thread fit? Will the fastener contact aluminium, stainless steel or another dissimilar metal?

Specify the required coating standard, thickness and test method instead of relying only on a colour description. Salt-spray hours can be arranged through a third party when the order requires documented testing.