Steel material is of utmost value due to its versatile usage. Stainless steel and galvanized steel are two of its types, differing in their properties. The debate between galvanized steel vs stainless steel has been ongoing for years. Many people favor stainless steel and consider it superior to galvanized steel.
However, galvanized steel also receives attention due to its lower rates. Manufacturers use this material to create budget-friendly parts a
nd projects. However, one can easily become confused when choosing between galvanized and stainless steel. In this article, I’ll dive deeper and discuss the differences between these two materials. Let’s begin!
Basic Rundown of Galvanized and Stainless Steel
This article explores the differences between galvanized and stainless steel. However, before discussing differences, let’s first understand their basics.
Stainless steel is an alloy consisting of multiple elements. Iron, carbon, chromium, and nickel are the primary ingredients. Notably, it contains 10.5% chromium, making this material a premium one. Due to the presence of chromium, stainless steel exhibits excellent corrosion resistance.
As you know, pure steel consists of carbon and iron. If you add chromium to this steel, it will become stainless steel. Pure steel has significantly compromised corrosion resistance. Parts made with steel can corrode quickly. However, the addition of chromium makes the steel more resistant to corrosion.
Galvanized steel is coated with zinc. This coating is applied by dipping carbon steel into the molten zinc. Therefore, the molten zinc comes into contact with the steel’s surface. Upon cooling and solidification, the molten metal forms a zinc layer on the surface of carbon steel. It acts as a barrier, making the steel corrosion-resistant.
This process, through which galvanized steel is produced, is known as hot-dip galvanizing. In simple terms, steel with a zinc coating is referred to as galvanized steel. It is affordable and offers resistance in the harshest outdoor conditions. However, you should not consider it a replacement for stainless steel due to its multiple limitations.
Differences Between Galvanized steel and Stainless steel
In the section above, I discussed the overview of these two steel types. However, galvanized and stainless steel differ from each other in many ways. In the section below, I’ll explain all those distinctions. Understanding these differences will help you choose the right steel type for your specific needs.
1- Composition
As I said earlier, galvanized steel is not a unique material. Instead, it is carbon steel that has a zinc coating on it. The composition of this galvanized material is the same as that of carbon steel. This carbon steel is dipped into the molten zinc. When removed, the zinc forms a layer on the surface of the carbon steel. The base carbon steel is typically made of carbon and iron.
Stainless steel is a unique alloy composed of various elements. It consists of carbon, iron, and chromium. Here is a table showing the chemical composition of stainless steel:
| Element | Percentage (%) |
| Iron (Fe) | 66–74% |
| Chromium (Cr) | 10–20% |
| Nickel (Ni) | 8–10.5% |
| Carbon (C) | ≤ 0.08% |
| Manganese (Mn) | ≤ 2.0% |
| Silicon (Si) | ≤ 1.0% |
| Phosphorus (P) | ≤ 0.045% |
| Sulfur (S) | ≤ 0.030% |
In the table, I mentioned a range of proportions for each element instead of exact quantities. The reason is that stainless steel has different grades, i-e. 304, 316, and 430. The proportion of each component varies from grade to grade. For example, grade 304 has 18% chromium, while 316 stainless steel has a lower chromium content of around 16%.
2- Rust Resistance & Durability
Stainless steel is a superior material in terms of corrosion resistance. The reason is that this material has over 10.5% chromium. This chromium reacts with oxygen and makes a unique layer of oxide. This layer, called chromium oxide, remains on the surface of the material. It protects the stainless steel from corroding.
Even with these significant scratches, it can repair itself. On the other hand, galvanized steel features a zinc coating. This coating can protect the material from corrosion. However, it starts to deteriorate over time and gets removed. After that, the material begins to corrode quickly. Therefore, I consider stainless steel a better option for corrosion resistance.
Due to its better resistance against rust, it lasts longer and is more durable. Therefore, stainless steel pipe manufacturers don’t even add a coating on these pipes. The reason is that the chromium material provides perfect protection against corrosion. There is no need to apply any additional coating or painting for rust protection on stainless steel pipes.
3- Appearance & Surface Finish
Stainless steel material comes with a natural shine. If you see it from a distance, it shines and gives a polished look. On the other hand, galvanized steel has a dull appearance and lacks sharpness. The zinc coating present on the surface makes it rough and less smooth.
Stainless steel can also undergo various surface treatments, including polishing and grinding. However, the galvanized steel has limitations due to the presence of a zinc coating. If you grind this material, its zinc coating will be removed. Additionally, it cannot be polished or painted, which is a big drawback.
4- Strength & Weight
Stainless steel has a higher proportion of nickel. The presence of it nicely increases the mechanical strength of this material. So parts made with stainless steel can withstand extreme loads and stress. On the flip side, galvanized steel is compromised in terms of its strength. It cannot withstand extreme tension and is prone to breaking.
However, this material is lighter than stainless steel. Parts made with this material are easy to carry and transport. However, considering the weight-to-strength ratio, stainless steel is a superior option. Its higher strength, combined with slightly higher weight, makes it stand out. The stainless steel sheets and pipe will perform better when used in extreme pressure conditions.
5- Lifespan & Scratch Resistance
Stainless steel offers a longer lifespan and greater resistance to scratches. The pipes made of stainless steel serve longer than those made of galvanized steel. Why? Because stainless steel has chromium, which protects this material from corrosion.
Additionally, it has excellent strength, which enables it to withstand stress easily. The chromium oxide layer present on the surface of stainless steel is very robust. It does not get scratched easily. Additionally, even if you scratch it, it can repair itself. Therefore, the stainless steel lasts longer and resists scratches.
On the other hand, galvanized steel has compromised corrosion resistance. The zinc coating present on its surface is weak and deteriorates quickly. The part made with stainless steel can remain in good shape in extreme conditions. Therefore, stainless steel is widely used in the manufacture of marine industry parts.
6- Weldability & Heat Resistance
The galvanized steel has lower heat resistance (200–250°C). During welding, excessive heat can cause the material to overheat and cause damage. So its welding process is very challenging. You’ll have to provide the right heat to melt the galvanized steel to create a joint. Additionally, this material has a zinc coating on its surface.
During welding, heat melts this zinc coating. As a result, fumes are released from the coating, which must not be inhaled. The stainless steel has excellent heat resistance (870–925°C). So melting is easier, and you don’t have to worry about overheating. Almost all grades of stainless steel material can be welded smoothly. You can use TIG, MIG, or laser welding to create a strong weld on this material.
7- Grades & Variants
Stainless steel is a versatile material and has multiple grades and types. The properties of each of those grades vary from each other. For example, 304 stainless steel is known for its ideal corrosion resistance. It contains a higher proportion of chromium (18%).
On the other hand, grade 316 has excellent mechanical strength. Similarly, stainless steel 430 grade has compromised corrosion resistance but is affordable. On the other hand, galvanized steel does not have such grades. It is a standalone material composed of carbon steel as its base and featuring a zinc coating. There are no particular types of this galvanized steel.
8- Cost & Applications
In the above sections, you’ll only read the downsides of the galvanized steel, right? When compared to stainless steel, this material lags. However, its lower cost is one of the factors that make it popular. Manufacturers use this material to make cheap and inexpensive parts and products.
Parts made with this material are not long-lasting but are inexpensive. Despite its compromised properties, its lower cost increases its usability. The stainless steel is more premium and expensive. It performs excellently in harsh conditions (such as moisture) or under extreme stress. This material is widely used in the construction and marine industries.
Here is a table showing the comparison of the application of stainless and galvanized steel:
| Galvanized Steel | Stainless Steel |
| Fencing and roofing. | Kitchen sinks and countertops |
| Street signs and outdoor poles. | Food processing equipment |
| Water pipes (older systems). | Medical and surgical tools |
| Car frames and body panels. | Exhaust systems and engine components |
| Cable trays and support structures. | Chemical tanks and industrial piping |
| Ductwork and HVAC systems. | Marine hardware (especially 316 grade) |
| Scaffolding and storage racks. | Architectural panels and railings |
Frequently Asked Questions
Is stainless steel completely rustproof?
No! However, this material can remain in good shape for several years due to its chromium oxide layer. Galvanized steel can start to corrode very quickly.
Which is better, galvanized steel or stainless steel?
Stainless steel is a superior option to galvanized steel. It offers better corrosion resistance, longevity, and excellent strength. The galvanized steel has a low price, which is its only advantage.
Is a galvanized chain better than stainless steel?
I recommend using chains made of stainless steel. This material is rust-resistant, ensuring chains don’t corrode quickly. Additionally, their strength and overall performance will also leave you impressed.
Concluding: Which Material Should You Choose?
The selection between galvanized and stainless steel is not very difficult. However, you must know what you need for the proper selection.
If you prefer quality and performance, I recommend choosing stainless steel. This material will last longer, offer corrosion resistance, higher strength, and top-notch weldability. However, the prices of stainless steel are very high, which can be a drawback.
If you have a tight budget, the galvanized steel can be considered. However, this material won’t offer an excellent lifespan. Additionally, their strength and rust resistance is also compromised, which is a drawback. Parts made with this material won’t withstand harsh usage or extreme stress. In my opinion, my vote goes to stainless steel material.