There are many different types of metal, each with its own unique properties. Choosing which is most appropriate for your gates means assessing all the relevant factors to identify the one most suitable to your needs.
Location
In coastal areas where damp, salty air increases the risk of corrosion, aluminium is popular. In places with many traditional property designs, you may choose bronze, or wrought iron gates such as those at //donkeywellforge.co.uk/what-we-make/wrought-iron-railings-bespoke-metal-gates to help maintain the historical character.
Durability
Steel is particularly well-known for its durability, especially if enhanced with powder coating or other surface treatments. Stainless steel is even stronger, and like aluminium