Aluminum and steel are two different elements having different physical properties. Aluminum is lighter than steel, and they two have different thermal conductivity. We get a lot of questions. One of them is, “can I use aluminum brazing rods on steel?”
Yes, aluminum brazing rods on steel is a well-known yet a little technical process for joining two metals. Aluminum’s melting temperature is 660 degrees Celsius, where steel gets melted at 1370 degrees Celsius. Therefore, the common approach of welding aluminum on steel can be difficult.
In this article, you’ll find why aluminum brazing is used and how to use it on steel. Moreover, we’re going to add some frequent queries to clear confusion and dilemmas.
Why Is It Difficult to Weld Aluminum and Steel?
Welding is always a convenient process for joining metals. But, in the case of aluminum and steel joining, welding is not near the best option. Adhesive bonding and mechanical fasteners are the two most used solutions for joining aluminum and steel.
The difference in thermal conductivity between aluminum and steel is the main obstacle to welding aluminum and steel. On the other hand, aluminum brazing is a safe option to consider for joining aluminum and steel.
If you need a quick solution to make the process easy and convenient, coating the aluminum and using the aluminum brazing to join the steel is the best option.
Where Can You Use Aluminum Brazing Rods?
“The right temperature is the key to join two metals together,” says TWI; The Welding Institute.
To know the proper use of aluminum brazing rods, you must find places where steel and aluminum are joined together. These two dissimilar metals are connected or welded with arc welding.
For a successful arc welding process, an aluminum brazing rod is important and somewhat mandatory. Benefits regarding the consistent ductility and strengths are the main reasons for which people use these rods.
How Can You Use Aluminum Brazing Rods on Steel?
There are two methods to use aluminum brazing rods on steel. The first is the aluminum coating on the steel, and the second one is bimetallic transition inserts. Both approaches will help you in getting the optimal result in arc welding.
Hot Dipping
Hot dipping; or coating with aluminum on steel is one of the most popular methods to use aluminum brazing on steel. This is also a fast method for joining aluminum and steel.
First, coat the steel and its surfaces with silver solder. Soldering will help to create a different thermal conductivity.
Second, you need to use aluminum filler alloy and weld the aluminum and steel together. Arc welding comes next, where the brazing helps to create a strong joint between two different metallic compounds.
Finally, let the joint get cold. When it is cold enough, the aluminum will get stick to the steel without further melting down or similar contexts.
One of the benefits of hot dipping or soldering the steel with silver is increasing the thermal conductivity without compromising steel’s ductility. For building and joining steel with aluminum in strong construction sites, this process is effective.
Also, hot dipping and using the coating help the brazing process to keep away from contamination. No external metal can enter or affect the process. The strength and ductility in ships and other construction sites are assured with silver soldering.
Again, hot dipping is a popular method in aluminum brazing because of its cost-effectiveness. A pack of aluminum brazing rods is enough to build a strong connection between aluminum and steel.
Bimetallic Transition Inserts
The next method where you can use aluminum brazing rods on steel is to use bimetallic transition inserts. These inserts do the tricks for joining aluminum with steel.
Bimetallic inserts have two portions or sides. One side is made of steel. Steel’s melting temperature is 1370-degree as we stated earlier once. On the other hand, aluminum’s melting temperature is 660-degree.
When one insert has two sides with different thermal conductivity, these will melt at a certain temperature. The insert works as a connector to connect between steel and aluminum. The aluminum portion connects aluminum, and the steel portion connects steel.
This technique to use dual metal inserts is also a familiar welding technique. The strength and other features such as ductility, flexibility, and internal thermal characteristics remain the same.
FAQs
Welding is necessary, and sticking aluminum brazing rods on steel is a complex welding trick. We get the following questions frequently. Let’s take a look at them.
Is brazing aluminum as strong as welding?
It’s a quick process to connect two different metals. If you need quick repairing, brazing aluminum is highly recommended. And it is as strong as welding. Brazing rods reduces contamination and keeps the natural strengths of the metal.
What temperature is required for brazing?
840-degree Fahrenheit or 450-degree Celsius is the required temperature for brazing. This helps the welder to get a good connection between two metals. Meanwhile, you may need to switch between 550 to 1400 degrees Celsius during aluminum and steel welding.
Can stainless steel be brazed?
Stainless steels can be brazed by maintaining appropriate temperature, aluminum rods, and arc welding. The compatibility between stainless steel and aluminum is the key factor to decide whether these two can be brazed or not. In the majority of cases, stainless steel (carbon-based) is brazed with aluminum brazing rods.
What are the benefits of brazing?
Brazing is helpful in terms of its low power requirements. The residue from brazing is less than any other welding method. Also, arc welding is a cost-effective welding method.