The production of almost every modern-day product involves the use of different metals. It is impossible to manufacture metal products without reshaping and joining metal pieces. The two well-known methods of joining metals are welding and brazing.
But how can you choose the most suitable method for your requirements from welding VS brazing?
When choosing any joining method, you should consider the assembly size and the thickness of the metals. Depending on the temperature your final product may endure, the process of joining changes. You should also consider if the joining will occur at some particular points or not. The overall cost and energy consumption are two other factors.
In this article, I have compared two commonly used methods of joining two metal objects. I have discussed all of the benefits and drawbacks of using welding and brazing methods in small and large-scale production. This article can be helpful to you if you are about to set up a manufacturing unit or want to quench your thirst for knowledge.
How Welding & Brazing Works?
To make metal pieces usable for humans, we need to cut and join them according to the engineer’s design. Two popular methods of joining metal pieces are welding and brazing. Below, I have elaborated on how these two methods do their job of joining metals!
How Welding Joins Metals?
In short, welding melts and fuses two particular points of two separate metal pieces to bond the two metal objects with each other. Usually, welders add melted filler metal at the jointing point. After the bonding between the two metal objects become so strong that you will find no difference between the two metal objects after the welding,
First of all, the welder melts the points to join the two metal objects. He has to use concentrated heat at a high temperature on the joining points. Different metals have different melting points. When the atomic cells at the joining points of the two metal pieces melt along with the filler metal, the welders hold them tight and cool them to make the joining permanent.
When To Weld Metals?
Generally, welders choose the welding method to join metals when the joining points are at least half an inch thick. Moreover, the joining has to be limited to a single area. Usually, welders do not use this method when there is a need for cosmetic joints because the bead of a welded joint is irregular.
Welders use the welding process frequently in the construction, transportation, and manufacturing sectors. Most repair shops also use the welding method to join metals. All the mega projects, like building structures, bridges, and railway tracks, need a welding method all the time.
How Brazing Joins Metals?
The brazing method is much different than welding. Welders do not melt the joining points of the metal objects they join when they use the brazing method. The welder creates a metallurgical bond between a filler metal and metal objects. Welders pass through the liquid filler metal at the joining point between the two metal objects in a capillary action.
The welder uses some heat on the base metals so that the filler metal instantly melts when it flows into the joining point. However, the brazing method does not require a high temperature on the metals. As a result, the brazing method requires much less power to accomplish the job than the welding method.
This method of joining metals is most commonly used in aerospace, automobile manufacturing, and electronics. The jewelry industry also needs to use the brazen method to bring aesthetics to their jewelry.
This method is helpful for joining different types of metal, like steel and copper. You can also join non-metal objects like graphite or diamond using this method.
Advantages & Disadvantages Of Welding
Each of the welding and brazing methods has its fair share of advantages and disadvantages. Welders choose a convenient approach according to the thickness of the metal objects. Let’s start by talking about what you can expect from welding.
Advantages Of Welding
Big construction projects and manufacturing factories frequently use the welding method to join metals. Because it is fast and suitable for circumstances where you need to attach some particular points to two metal bodies.
For Joining Small Area Of Metals
In the welding process, intense heat is applied to a single point to melt the area of the metal body. If you do not have to join a large portion of the joining metal bodies, it is always good to use the welding process.
The localized high heat of the welding method can join two metal pieces at a single point. It is also known as the “electrical resistance welding approach.”
For Permanent Joining
The joining of the welding method is permanent. After the welding, the atomic form of the metals in the joining area becomes as strong as the metals themselves.
That is why welders appreciate the welding method when they need a permanent metal joining. You must use the welding method to join the metal structures of a building construction site.
The Economic Method
The cost of using the welding method is much less than other methods of joining metals. That is why large-scale industries always try to use this method to minimize production costs.
The welding process maximizes the profit margin by reducing the time of manufacture. It is a quick process to weld thousands of metal products in a large-scale automated production plant.
Easy To Automate
Another advantage of using a welding method is the convenience of automation. In most cases, the point of joining a metal body is precise. The required temperature to melt a specific type of metal is also fixed.
So, it is very convenient to run an automated manufacturing plant using the welding method when you need to produce thousands of products in a limited period.
Recommended By The Experts
Engineers recommend the welding method if the metal products need to withstand a high temperature.
Metal objects like the engine cylinders, propellers of an airplane, or space rockets need to go through high temperatures. The metal products will not function properly if the manufacturer joins the metals using any other method than welding.
Disadvantages Of Welding Method
Despite all the mentioned advantages, there are some disadvantages of the welding method too. Welders avoid this method if the joining needs to be done in a larger area since it only has a localized approach to joining metals.
Require More Energy
Metals are usually hard objects. If you want to melt them down, you need a high temperature. And a welder can generate high temperatures only by using an intense volume of energy.
Most of the metal’s melting point starts from 2,000 °F. Since the welding method needs metals to melt first, the welding machine generates high temperatures by consuming a high volume of electricity.
Not Suitable For Linear Joining
Imagine a situation where you need to join two metal pieces side by side. In that case, the welder will need to melt one side of both the metals if you use the welding process. It increases the cost and time of joining them.
The pin-pointed approach of the welding method does not work efficiently in that scenario. Other metal joining methods, like brazing, are more convenient for the linear joining of metal objects.
Not For Thin Metal Sheets
To join two metal pieces with the welding process, the welder has to make sure that both of them have a minimum thickness of half an inch. Otherwise, welders would destroy the structure of the metal bodies during the welding process.
So, if you are joining thin metal pieces together, you cannot use the welding method. It will damage the metals. That is why electrical plants mostly use brazing or soldering in their manufacturing plants.
Not for Ornamental Joining
Usually, ornamental joining involves sophisticated metals. These soft metals get distorted easily at high temperatures with excessive heat. That is why you will see limited use of the welding process in ornament-producing plants.
Imagine the fascinating decorative metal products like the silver utensils in your house. It would never become so smooth if the manufacturer tried a welding method to do all the decorations.
Needs Post-Processing Heat Treatment
Another disadvantage of using the welding method to join metals is the post-welding treatment. When you melt metal objects and join them at particular points, you need to cool the metal immediately to ensure the joint stays permanently.
This heat treatment increases the cost of production. Besides, it consumes some skills and time too. That is why most manufacturers do not wish to use the welding method if it is possible to avoid it.
Cannot Join Dissimilar Metal Objects
Assume that you need to join two metal objects, where one is steel-made, and the other is copper. In that case, you cannot use the welding method because it can only join metals of the same atomic structure.
While melting two metal parts, the welding machine uses the same temperature. However, different metals have different points of melting. That is why the welding method will not work efficiently in that scenario.
Involves More Risk Factors
While generating and using high temperatures, the welding method raises the risk of fire accidents. Besides, there can be some fatal accidents while joining metals in this method if the electricity or gas supply malfunctions. Moreover, the sparks from the welding process can fly up to 35 feet from the spot of welding. It increases the risk of fire accidents.
If the welder is not wearing proper protective gear, he can burn his hands with the high temperature of the welding machines. Moreover, there are also chances of electrocution for the welder and the people around a welding site. The danger increases if the welder fails to maintain proper ventilation in the welding area throughout the operation.
The Health & Environment Concerns
The welding process creates large amounts of harmful gases and fumes. So, the welder is always at risk of getting sick with severe diseases. The possibility is minimal with other types of metal-joining methods.
The welding method also pollutes the environment. It continuously produces some green gas, which is responsible for the depletion of the ozone layer in the sky. That is why environmentalists are always so vocal about containing the use of the welding process.
Advantages & Disadvantages Of Brazing
Brazing also has some advantages and disadvantages. Let’s take a look at some of them.
Advantages Of Brazing Method
Brazing is gaining popularity as an alternative method of joining metals. It only heats the filler metals to make them a bonding agent between two metal bodies. It is very convenient to join two different types of metals. However, the brazing method has many other advantages than joining different metals.
The brazing method does not require melting down the two metal objects to join them together. All the variants of the brazen methods—torch brazing, vacuum brazing, furnace brazing, or induction brazing only generate around 842° F of temperature to melt the filler metal. It is almost one-fourth of the temperature that a welding method would produce.
As a result, the brazing method needs much less energy to do its job. Hence, the manufacturer needs to bear much less burden of production cost if he can use this method in his plant. This feature of less energy consumption has made this metal-joining method a greener approach in manufacturing. However, the brazen method needs more energy than the soldering method.
Cleans The Surface
Generally, the filler metal flows with a flux in the brazen method. These fluxes have another utility besides facilitating the easy flow of the melted filler metal. It also cleans both the metal surfaces.
Cleaning the metal surfaces from any foreign particles is crucial before joining them. It ensures a durable and solid joint. Finally, the cost of production reduces since the manufacturer does not need to use any other cleaning agent.
Can Join Dissimilar Metals
Its ability to join different kinds of metals together has made the brazen method very popular among manufacturers.
This diversity of the method has made it possible to produce many integrated products and machinery that were never possible before the invention of the brazen process.
Less Risky Than Other Methods
Since the brazing method produces lower temperatures than the welding method, the risk of fire accidents due to electric malfunction is much lower. Besides, the chances of the welder getting hurt during his job are very thin with the brazen method.
Moreover, compared to the welding method, this method produces low amounts of harmful gases and fumes. From the perspective of health and the environment, this is very welcoming.
Low Training Cost
Compared to other metal joining methods, the skills that a worker needs to apply to this method are very easy to learn. It lowers the training cost of a manufacturer significantly.
The time of the training period for the method is also shorter than the welding method. It ensures the availability of a good number of welders in any given condition.
Disadvantages Of Brazing
However, there are still some disadvantages to the brazing method. That is why not all commercial entities can accept this method to join different metals. The disadvantages of this method are described here.
Compared to the welding process, the joints the brazing method can make are weaker. The brazen method is good for joining metals to create sophisticated products. However, if the metal product has to withstand a lot of pressure, the joint may break.
While joining the metal pieces with the welding process, the welder makes a permanent bond between the two metals by melting and uniting them at the atomic level. So, the joining becomes an integrated part of the two metals. However, it is not true about the brazen method.
Not For High-Temperature Products
Like an engine cylinder or a spaceship, if the final product needs to endure extreme temperature, the brazen method is not enough to hold the two metal objects together.
In that case, it is better to go with the welding method, where you make the joints permanent by melting the atoms of the metals at high temperatures.
Toxicity Of The Fluxes
Welders need to use fluxes to ensure a free movement of the melted filler metal between the two metal objects to be joined. So, fluxes are an inseparable part of the method.
Welders need to use fluxes to ensure free movement of the melted filler metal between the two metal objects to be joined. So, fluxes are an inseparable part of the method.
The extensive use of both the welding and brazing methods in different industries indicates that both of the metal-joining methods have certain utilities. So, before choosing any one of the methods, you should make an elaborate comparison of welding VS brazing. I hope this article has helped you with your studies of the two methods.