Brass vs bronze

Not referring to strength differences of brass & bronze, but non structural components made in brass when used in saltwater environment.
Not something that’s constantly submerged in salt water.

Is the alloy of brass used for saltwater boat components different than general purpose brass to prevent the brass from corroding?

I thought that brass didn’t fair well in saltwater boat environment, so bronze alloy of some type is better.

But I see some parts for boats made of brass from reputable companies, so figure the brass would be appropriate for some things.

For example some portholes are offered in brass and some in bronze (don’t know what alloy of bronze) and sink faucets (boat galley) are made in brass.
Is the brass alloy different than yellow brass, or what keeps the brass from deteriorating in saltwater boat.

Just trying to understand the appropriateness of brass in some parts.

Cheers, Allen

 

I'm not an expert, but in the 1800's they used a special alloy of brass they called "marine brass," typically with a higher zinc content. These days there is also what they call "Naval Brass," which is 59% copper, 40% zinc, 1% tin and small amounts of lead. In all eras of history though, there was a lot of use of recycled brass.

What is Naval Brass? - National Bronze Manufacturing https://www.nationalbronze.com/News/what-is-naval-brass/

These days it looks like they typically use "silicon bronze" for boat fittings, since it is very corrosion resistant:

The Revived Art of Brass and Bronze Marine Hardware https://copper.org/consumers/arts/2008/march/revived_Art%20_Brass_Bronze_Marine_Hardware.php

It also looks like the use of aluminum in the alloy helps with corrosion:

Brass Characteristics and Composition https://www.christinedemerchant.com/brass.html

Red brass has very little zinc (up to about 10%), white brass has a bit more (20-35%), and yellow brass has the most (up to 30-40%). As you see above, naval brass would be a kind of yellow brass. You need a bit of tin in it to prevent the zinc from leaching out with seawater though, so I wouldn't get just any yellow brass for fittings.

These days, as with the silicon and aluminum above, you can get all kinds of alloys for all kinds of purposes. Provided you get it from a company that manufactures marine fittings, I would presume they did their research, and use an alloy that's suitable for the sea.