Aluminum Vs Stainless Steel Corrosion – Which is More Durable?

Are you confused between aluminum vs stainless steel? No worries. You have come to the right place. I find, most people asked, about these two metal corrosion, and it’s obvious to get confused. Because, both are metal, and we know, metal creates the same kinds of corrosion. But, our assumption is wrong. Yeah, both create the same kinds of corrosion but, their format and causes are different. 

Aluminum and stainless steel are different metals. Aluminum steel is made with aluminum alloy and coated with silicon alloy. Whereas, stainless steel is formed with chromium that prevents rust.

Aluminum Vs Stainless Steel Corrosion

Aluminum Corrosion

Aluminum is a reactive metal and a passive metal, it creates corrosion when its molecules into its oxides degrade its physical and chemical properties.

Aluminum corrosion is of many types. In the article, I will discuss the most common types.

Galvanic Corrosion

Galvanic corrosion occurs when aluminum connects to noble metal. The noble metal is a less reactive metal than aluminum. The reactivity depends on its position in the electrochemical series. The results of corrosion will be worse if the metal is far away from aluminum in the electrochemical series.

Aluminum and brass are contacted with each other and placed together in seawater and formed in a galvanic cell. This galvanic cell in other environments leads to galvanic corrosion.

Atmospheric Corrosion

Atmospheric corrosion is the most common corrosion of aluminum. It occurs from the result of exposure to natural elements. Atmospheric corrosion occurs due to dry, wet, damp, and uneven moisture in the environment. When the environment is closed down and doesn’t get air or light, it occurs.

Pitting Corrosion

Pitting corrosion is like a small hole in the surface. The Pitts do not destroy any product rather it is an aesthetic issue but if the surface presence is critical it can lead to failure. 

Pitting corrosion occurred in the presence of chloride. And, the corrosion can be worse if there are alkaline and acidic salts. 

Crevice Corrosion

A crevice is a form of local corrosion process in corrosion materials. Mistakes in overlapping materials or unintentional design can lead to the formation of the crevice. As a result, the seawater collected in those packets can cause crevice erosion.

A small gap between the bolt and the structure creates a type of corrosion. With increasing time, the aluminum dissolves from the material, and seawater seeps into it. This ionic aluminum absorbs oxygen from the surrounding air and hydroxide ions from the electron to form aluminum hydroxide.  This oxygen reduction in the presence of chlorides creases crevices corrosion.

Stainless Steel Corrosion

Stainless steel is the format of durable metal. It makes the substance rust-resistant. However, corrosion can’t be neglected totally. It can create in many ways. We can keep rust-free by taking some preventive measures. Well, stainless steel is of various styles. In the article, I’ll discuss the most common ones.

Pitting Corrosion on Stainless steel

The presence of chloride or salt and bleach creates pitting corrosion on stainless steel. The lack of oxygen causes chloride ions. You can prevent pitting corrosion by choosing steel that comes with more resistance to attack.

Crevice Corrosion on Stainless Steel

Stainless steel required a huge amount of oxygen to make a passive layer on the surface. The tight crevice corrosion can’t gain oxygen thereby causing or attacking rust. So, you can avoid it by sealing crevices with a flexible sealant.

General Corrosion on Stainless Steel

In general, stainless steel does not corrode as much as ordinary carbon and alloy steels. However, with the help of some chemicals, mainly acids, the passive layer can be attacked uniformly depending on the concentration and temperature, and metal damage is distributed over the entire surface of the steel. Some contractions of hydrochloric acid and sulphuric acid are particularly aggressive towards stainless steel. The corrosion can be prevented by making it destructive.

Galvanic Corrosion on Stainless Steel

If two different metals get in contact with each other and also with electrolytes, it forms a galvanic cell. You can prevent it by separating the metals and combining them with non-metallic rubber.

Final Verdict

So, the above are the differences between aluminum vs stainless steel corrosion. I hope, now, all your confusion has arisen, and you get a complete idea regarding these two metals. Now, to buy anything or to keep your metallic substance rust or corrosion-free, it will help you.

I'm Melanie Dobbs and I am Chief Content Writer and Editor at Get Review Today.

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