Can stainless steel and aluminum be used together?

Galvanic corrosion occurs when stainless steel and aluminum (an anode and a cathode) come into contact with each other and an electrolyte. Electrolytes can be environmental factors such as humidity or rainwater. When these factors come into play, electron transfer will begin to occur. Depending on the level of resistance in an electrolyte, this transfer can happen much faster. This is why salt water, an electrolyte with a very low resistance, is a common factor when considering what product to use. Due to this, it is incredibly important to consider what material you are going to use in an environment.  When working with a marine, salt water environment, you even need to consider the type of stainless steel you are using.

How to stop galvanic corrosion？

There are a few steps you can take if you MUST use these materials together.

Add an insulator between the two materials so they no longer connect. Without that connection, the transfer of electrons cannot occur. Well nuts are a commonly used fastener to help separate materials that can suffer from galvanic corrosion.

Use materials with the same potential. Metals with the same corrosion resistance are typically ok to use together.

If you are in a situation where only one of the materials will come into contact with an electrolyte then transfer of electrons will not occur.

If there is a coating on the cathode it can prevent the transfer through increased resistance.

Consider your environment before installing. Choose materials that will work for your environment.

Coat or paint your assembly (completely) so that the electrolyte cannot make contact with the materials.

Use neoprene EPDM or bonding washers as a barrier in between the metals.