Will stainless steel react when in cotact with aluminum?

Answer 1

Not usually, but this can vary by alloys. There are many dozens of Stainless Steels and hundreds or more Aluminum alloys. The common as you can see in chart are very reactive with many steels and other metals.

Your asking about "Galvantic Response". To prevent this insulate with some material.

= CORROSION: GALVANONIC CORROSION = When two different metals are immersed in a corrosive solution, each will develop a corrosion potential. If the corrosion potential of the two metals is significantly different, and they are in direct contact and immersed in an electrolyte, the more noble metal will become the cathode and the more active metal will become the anode. A measurable current may flow between the anode and the cathode. The corrosion rate of the anode will be increased and the cathode decreased. The increased corrosion of the anode is called "galvanic corrosion". In order for galvanic corrosion to occur, three elements are required. 1) Dissimilar metals

2) Metal-to-metal contact

3) Metals in the same conduction solution (usually called an electrolyte) This can be air/water or moisture no just "solutions".

If any of these elements is missing, galvanic corrosion cannot occur. If, for example, the direct contact between the two metals is prevented (plastic washer, paint film etc.) there cannot be galvanic corrosion. The greater the corrosion potential of each metal (the more active or more noble) the greater the potential for corrosion. The "galvanic series" has been developed to list the various metals in order from most active to most noble:

SCALE:

More Anodic |

Magnesium

Galvanized Steel

Aluminum Mild Steel Low Alloy Steel Cast Iron Lead Tin Muntz Metal Yellow Brass Red Brass Copper Aluminum Bronze Silver Stainless Steel (430) Stainless Steel (304) Stainless Steel (316) Monel Silver Titanium GOLD

|

V

More Cathodic

The greater the separation between the two metals listed, the greater the corrosion potential. For example, if zinc (think galvanized steel) which is an active material and near the top of the list and stainless steel, a noble metal and near the bottom of the list were in direct contact and in the presence of an electrolyte (water), galvanic corrosion will probably occur.