When it comes to welding, there are many different types of welders and welding processes. Some people mistakenly believe that TIG and cold welding are the same processes, but they are quite different.
The main difference is that TIG welding uses heat to weld metals together, while cold welding does not. Cold welding is often used for joining dissimilar metals or when a very strong weld is needed. However, it’s important to note that cold welding can only be done on clean, polished surfaces.
Both of these methods have their own unique benefits and drawbacks, so it is essential to understand the difference before deciding which one is right for you. In this blog post, we compare and contrast TIG and cold welding. Let’s get started!
What is Cold Welding?
Cold welding is a type of welding that uses little or no heat to join metals together. Instead, cold welding relies on pressure and friction to weld two pieces of metal together.
This method is often used for joining dissimilar metals, as there is no risk of contamination from the welding process. Cold welding can also be used when you need a solid weld, as the welding process creates no heat-affected zone (HAZ).
There are two main methods of cold welding: cold metal transfer and contact welding. Let’s take a closer look at each one.
The first method is contact welding. In this process, both pieces of metal are cleaned, and the oxide is removed. They are then placed in direct contact with each other, and pressure is applied with enough force to cause the metals’ grain to bond.
The second method is cold metal transfer (CMT), which is a low-voltage, low heat technique for different welding types of metals with various thicknesses. This process was primarily used on thin sheet metal, but it’s also used on thicker materials.
When metals are overheated during traditional welding processes, their structural properties can compromise, resulting in distortion or cracking.
However, CMT helps limit this by using only the minimum amount of heat needed at any given time, ensuring better quality welds without adversely affecting the material structural integrity.
Cold metal transfer is often used in applications where a high degree of accuracy is required, such as manufacturing medical devices and microelectronics.
The main difference is that TIG welding uses heat to weld metals together, while cold welding does not. Cold welding is often used for joining dissimilar metals or when a very strong weld is needed.
However, it’s important to note that contact cold welding can only be done on clean, polished surfaces. – so, if you’re looking to weld something dirty or rusted, TIG welding is your best bet.
Where is Cold Welding Used?
Cold welding is a versatile process that has a wide range of applications. It can be used for industrial and commercial purposes and is especially well-suited for fabrication.
One of the most common applications for cold welding is in the automotive industry. This process is often used for joining together various parts of a car. Another popular application for cold welding is in the aerospace industry, and it’s often used to bond metal aircraft components and items used in the space industry.
Sometimes, heat can be used in pressure welding, but it is used in order to make the metal more malleable, but the material is not molten. Also, cold welding is used in underground pipelines, which transport flammable products. This ensures that no explosion due to heat occurs during soldering.
In addition, cold welding is applied to various cables to unify parts produced with different metals, such as copper and aluminum.
Why is it Called Cold Welding
Since cold welding does not depend on heat to achieve its final result and change the state of the items, the welded material remains in a stable condition throughout the process; that is why it is called cold welding.
Cold pressure welding is nothing more than a bonding process. Two pieces are transformed into one through intense pressure applied by dies or rollers, without the aid of thermal energy and under normal ambient conditions.
What Metals can be Cold-welded?
Not all metals allow cold weld fusion due to their properties and the amount of oxygen within their outer layers. In addition, for the conservation of the weld resulting from the cold pressure process, the parts mustn’t be exposed to oxygen-rich environments.
Cold pressure welding is restricted to non-ferrous materials or, at best, soft iron that does not contain carbon. Most non-ferrous metals can be cold-welded. Although copper and aluminum are the most common, various alloys such as Triple E, Constantan, 70/30 brass, zinc, silver, and silver alloys, nickel, gold, and many others have good weldability.
Plated wires, including tinned copper, silver-plated and nickel-plated, can all be welded together or to plain copper.
Can Non-metals be Cold-welded?
The simple answer is NO, but there are also certain conditions and types of non-metals such as glass which can be cold-welded, providing the vacuum, exact force, and a spotless surface, which is a rare phenomenon for non-metals.
Is Cold Welding Strong?
Cold welding provides one of the most solid welds for creating metal-like bonds, i.e., the resulting welds have the same bond strength as the original material. This feat is challenging to recreate in metallurgy.
For example, cold welding is known for its ability to weld aluminum and copper, which are often challenging to fuse with other forms of welding techniques. However, the bond created between the two materials by cold welding is very strong.
What Surface Preparation is Done Before Carrying out Cold Welding
Scientifically, the cold-welding process is called solid-state diffusion, and it uses pressure to create welds. When two materials are pressed together, they rarely weld together.
This is mainly because there is an oxide layer or a thin barrier on the surface of the materials. Cold welding overcomes this problem by preparing the metals before they are welded.
The preparation process involves cleaning or brushing the metals so that the top oxide layer or barrier is removed. This is accomplished by decreasing the metal and then brushing the wire.
Once the desired surface cleanliness is achieved, both materials are mechanically pressed with just the right amount of force. The amount of force depends on the material itself, as some materials can only weld at high pressures.
What Gas do you Use for Cold Welding?*
In cold welding, pressure is used to create welds; therefore, no gas is used. This is mainly because there is an oxide layer or a thin barrier on the surface of the materials. When this barrier is removed by cleaning and decreasing, materials can be mechanically pressed with just the right amount of force to weld.
However, with CMT, a process of MIG welder, a shielding gas Helium or Argon is used depending upon the metal.
What is TIG Welding?
TIG welding (tungsten inert gas) is a process that uses a non-consumable tungsten electrode to produce heat. The weld puddle is protected by an inert shielding gas, which helps to prevent oxidation and contamination.
TIG welding can be used in conjunction with a filler metal. It is most often used for thin metals, as it produces a clean weld with minimal distortion. However, you can also use it on thicker metals if the correct settings are used.
What is Cold TIG Welding
Cold TIG welding is a process, also known as micro-welding, performed on materials where a low heat weld is required. It is a process to fuse, usually soft metals with only a “zapping effect” of heat.
Can you Cold Weld with a MIG Welder
MIG welders are a type of welding that uses an electrical arc to fuse two pieces of metal. You can use a MIG welder to weld different types of metals. Many MIG welders can also be used for cold metal transfer welding (CMT), a cold welding process where you join two pieces of metal with low heat.
CMT, being an arc welding process, uses an electrode wire controlled by electronics with which the heat factor is reduced by almost 90% to make a perfect cold weld. However, this method also requires great skill in equipment handling and the implication of the process.
Is Cold Welding Easy
Cold welding isn’t easy because you must prepare the joined surfaces just right to achieve the desired union. In most cases, it’s challenging to get your workpieces free of irregularities and contaminations.
Why does cold welding happen?
During cold welding, the atoms from the surfaces of two metals join together to create a strong bond. For this phenomenon to occur the oxide layers of each piece must be removed so the atoms can join.
So, what is the difference between TIG welding and cold welding? The main difference is that TIG welding uses a tungsten electrode to create intense heat, while cold welding uses little or no heat. This makes TIG welding a more precise process, as you can better control the welded area.
However, because it uses heat, TIG welding can also cause damage to the materials being welded. Cold welding is less precise but doesn’t cause any material damage. Ultimately, which type of welding you choose depends on your project requirements. If precision is key, go with TIG; if speed is more important than precision or you need to join two very different types of metals together, cold welding might be a better
There are TIG welding machines with AC and DC current options and also have a cold setting to fuse metals that otherwise could melt due to excessive heat. The “cold” function, being a manual process, should be used with care and skill to obtain the desired result; otherwise, the metals can melt or bend and or can extend.