Galvanized Steel Vs Aluminum: The Complete Guide
Before you decide whether to use galvanized steel or aluminum for your applications, read this guide. It has all information about these materials including benefits, physical properties, chemical properties, mechanical properties and applications, just to mention a few.
What Is Galvanized Steel?
Galvanized steel is a metal with a layer of zinc coating. This layer of zinc is added to the steel to protect it from rusting. The main purpose of the zinc coating on galvanized steel is to increase its lifespan.
Alloying Element In Galvanized Steel Vs. Aluminum
You can add alloying elements to the materials to increase their strength or other properties such as corrosion resistance. Aluminum has several alloying elements. They include; copper, silicon, manganese, zinc, lithium, magnesium, lead, chromium, boron, zirconium, tin, titanium, bismuth and vanadium. The above alloying elements have their purposes and what they add to the main material.
Aluminum, copper, cobalt, nickel, molybdenum, titanium, manganese, chromium, and niobium are the alloying elements in galvanized steel. The alloying elements are added to galvanized steel to improve its mechanical and chemical properties.
Thermal Conductivity: Galvanized Steel Vs Aluminum
Regarding thermal conductivity, aluminum is much more conductive than galvanized steel.
Galvanized steel is about four times less effective in thermal conductivity than aluminum.
Strong metallic bonds hold together metal particles, resulting in aluminum’s perfect conductivity.
For applications that involve thermal conductivity, it is better to go with aluminum other than galvanized steel. One of the properties of aluminum is low density. With low density comes good thermal conductivity. Overall, aluminum is among the best metals that conduct heat. For this reason, you can widely use it in transmission lines.
Fabricating Galvanized Steel Vs Aluminum
There is a big difference when it comes to fabricating galvanized steel and fabricating aluminum. The process of fabricating galvanized steel is a lot cheaper compared to that of aluminum. Aluminum boasts low density, which means it is a good thermal conductor. This has a higher heat exchange than galvanized steel.
The good news, depending on your production needs, you can machine, cut, shear, bend, stamp, mill, drill, or even weld the two metals. You can learn more about metal fabrication.
Corrosion Resistance: Galvanized Steel Vs Aluminum
Corrosion resistance is one of the most important properties of any metal. A metal that can resist corrosion is much more advantageous than one that cannot.
Among the many properties of aluminum, corrosion resistance is one of them. Aluminum can resist corrosion far greater than galvanized steel. It would be best if you use aluminium rather than galvanized steel for any application that may involve contact with water or moisture. The aluminum’s chemical composition contains some alloys that are great at resisting corrosion. When using galvanized steel, you should avoid contact with moisture and water as much as possible.
Welding Galvanized Steel Vs Welding Aluminum
Welding aluminum is a lot easier than welding galvanized steel, but it also comes with some challenges. The process of welding galvanized steel requires extra caution. This is because it produces toxic fumes, which can harm the environment or human beings. This means during the welding process of galvanized steel, you must put on proper protective clothing.
Some features of aluminum, such as high thermal conductivity and low melting temperature, make it easier to weld than galvanized steel. Aluminum is also more malleable and elastic than steel, making it more flexible.
Aesthetics: Aluminum Vs Galvanized Steel.
If you like to paint on the surface of the metal to make it more beautiful, then you can use either aluminum or galvanized steel. Aluminum is far more attractive when it comes to aesthetics. It has a shiny, clean silver-whitish look which makes it more beautiful. Moreover, aluminum has a wide variety of colours and finishes which you can use to meet the aesthetic demands.
Galvanized steel has a vintage look which is dull, making it not suitable for applications that require its aesthetics. Additionally, galvanized steel can be used for exterior design purposes instead. Aluminum has excellent corrosion resistance making it the best choice for kitchenware or fencing.
Strength Of Galvanized Steel Vs Aluminum
If you need a metal between the two that can be used frequently or withstand hard impact, you better go with galvanized steel. Galvanized steel is a lot stronger than aluminum. Aluminum is a lightweight metal making it weaker compared to galvanized steel.
For applications that involve hard impact strength, you should pick galvanized steel. It would be best to keep in mind that strength comes with heaviness. Aluminum can, however, become stronger when the temperatures are low than when they are high.
Brittleness Of Galvanized Steel Vs Aluminum
Galvanized steel is far much stronger compared to aluminum. This is because aluminum is a lightweight material, whereas galvanized steel is heavy. In very low temperatures, the strength of aluminum and its alloys adds up. This means in extremely low temperatures, aluminum is less brittle.
However, galvanized steel is brittle in low temperatures, especially when exposed to the temperature for a long. Regarding the brittleness of galvanized steel compared to that of aluminum, aluminum is less brittle in low temperatures. In high temperatures, the brittleness of aluminum is higher than that of galvanized steel.
Malleability Of Galvanized Steel Vs Aluminum
Regarding malleability, aluminum is more stretchy and malleable than galvanized steel. It is important to note that galvanized steel is a sturdy and resilient metal. You cannot punch it to the same uttermost dimensional limits as aluminum without it splitting or cracking during the spinning procedure.
Aluminum is lighter and much more flexible than galvanized steel, making it malleable. This aluminum property makes it easier to fabricate than galvanized steel. You can easily make aluminum into a new shape without breaking it.
Magnetic Properties Of Aluminum Vs Galvanized Steel
Aluminun is a non-magnetic metal, and this means it has no magnetism. On the other hand, galvanized steel is magnetic. Galvanized steel is magnetic mostly because of the steel in the base. So if you are ever to choose between the two, you have to check whether the application requires magnetism or not. If you plan to use electric or mechanical appliances, use galvanized steel instead of aluminum.
Resistance To Temperature: Aluminum Vs Galvanized Steel
Aluminum has better temperature resistance compared to galvanized steel. Aluminum boasts low density, which means it is a good thermal conductor. This has a higher heat exchange than galvanized steel. If your application requires high temperatures, you should use aluminum rather than galvanized steel.
Types Or Grades Of Aluminum
- Alloy 1100 – Alloy 1100 is a commercially pure aluminum. It is supple and malleable and has is very easy to work with. It is also able to resist corrosion perfectly.
- Alloy 2011 – This grade boasts of properties such as high mechanical strength and perfect machining capabilities. If you are dealing with parts that have a lot of details and are complicated, Alloy 2011 is the best choice.
- Alloy 2024 – One of the properties of this grade is high-strength and excellent fatigue resistance. It has relatively low corrosion resistance.
- Alloy 3003 – When it comes to aluminum alloys this is the most popular grade. It is a commercially pure aluminum and is stronger than the 1100 grade. It has perfect corrosion resistance and is easy to work with.
- Alloy 5052 – Its fatigue strength is higher than most of the other grades. Alloy 5052 has good resistance to the marine atmosphere and saltwater corrosion. It offers weldability and excellent formability.
- Alloy 6061 – this grade boasts of most of the good properties of aluminum. It is the most versatile of the heat-treatable aluminum alloys. It has the best mechanical properties and is also resistant to corrosion.
- Alloy 7075 – It has a perfect strength-to-weight ratio. It is one of the highest-strength aluminum alloys available.
Types Of Grades Of Galvanized Steel
The types of grades of galvanized steel according to ASTM A653-09 are the following;
- Grade 33
- Grade 37
- Grade 40
- Grade 50
- Grade 80
- Grade CSA
Chemical Composition On Galvanized Steel Vs Aluminum
Chemical composition refers to the setup and the number of chemical elements in a material. Any element’s chemical composition determines the properties of the given material.
The chemical composition of galvanized steel consists of; carbon 0.20, phosphorus 0.10, manganese 1.35, and sulphur 0.04.
On the other hand the chemical composition on aluminum includes the following; vanadium 0.05, silicon 0.25, zinc 0.05, copper 0.05, titanium 0.03, magnesium 0.05, iron 0.04, manganese 0.05.
Galvanized Steel Manufacturing Process
The manufacturing process of galvanized steel involves a few steps. Listed below are the steps;
The pretreatment – this process is where you can remove any contaminants on the surface of the material. Use an alkaline solution to bring about an electrochemical reaction.
Annealing – annealing involves changing or bettering the material properties of the material after the pretreatment process.
Hot-dip galvanizing – The steel is submerged into molten zinc to coat the steel at this step. You should remove excess zinc is, and remain with the required amount.
Galvannealing – this step involves coating with an alloy. You can achieve this by heating a surface that has already gone through the hot-dip galvanizing with zinc.
Chemical treatment – at this step, the galvanized steel undergoes chemical treatment to ensure a very good finish and a flat surface.
Inspection – this is the last step, and it is very important. Check the galvanized steel to ensure it is of the best quality and all the specifications have been met.
Advantages Of Aluminum
- Aluminum is highly resistant to corrosion
- Aluminum is a superb reflector of visible light as well as heat
- Aluminum has an exceptional function of ductility
- It is light in weight. It is about a third of steel.
- You can recycle aluminum fully without downgrading its features
- Aluminum has excellent thermal and electrical conductivity
- Aluminum has a soft surface which is easy to clean
Advantages Of Galvanized Steel
- Galvanized steel has a high tensile strength
- It is cost-effective
- Galvanized steel is durable
- Galvanized steel is a highly sustainable material
- It is resistant to alkalis
- Galvanized steel has good impact resistance
- Excellent flame retardancy
Disadvantages Of Aluminum
- Its lightweight property makes it easy to dent, deform and even scratch
- Aluminium is far more expensive compared to other materials such as steel
- Welding aluminum is a long and pricey process
Disadvantages Of Galvanized Steel
- Can rust easily compared to aluminum
- Becomes the second choice in aesthetics compared to aluminum
- Has a very low thermal conductivity
- It has a very rough surface. The rough surface makes cleaning it hard.
Applications Of Galvanized Steel Vs. Aluminum
- Automotive and transport industry
- Packaging industry
- The medical and pharmaceutical industry
- Aerospace industry
- Marine applications
- Household and industrial appliances
- Construction industry
- Food and catering industry
- Telecommunication industry
- Agriculture industry
- Construction industry
- Automotive industry
- Wind and solar industries
- Household appliances
People Also Ask:
It is impossible to give a straight answer to this question. This is because the two materials offer different benefits depending on the application. Overall, aluminum is the most preferred material.
Yes, galvanized steel is a lot heavier than aluminum. Since galvanized steel is stronger than aluminum, it makes it also heavier.
Galvanizing steel increases its durability. An estimate shows that galvanized steel can last about 34 to 170 years. The coating gives the steel very good protection.
It is crucial to keep it away from substances like acid rain.
You should ensure it is away from the substance with a PH lower than six or more than 12.