The joining of the metal with little or no heat is called cold welding. It is an interesting method of welding where physics and an understanding of material science work.
Here we will be learning: What is cold welding? How does it work, and what metals can we weld?
How do you define cold welding?
The process of cold welding needs no heat input to join the metal workpieces together. The metal is not molten at any stage and remains in a solid state. Thus, cold welding is labeled as a solid-state welding process. The necessary energy to join the metal is applied in the form of pressure. Cold welding never has the metal in a molten state as compared to fusion welding or arc and friction welding.
The pressure application brings the metal surfaces as close as possible. The extent of pressure makes the nanodistance irrelevant; the atoms from the metal jump from one sample to another. This leads to a near-perfect joint with no consequences, and two metal pieces become a homogenous bunch.
To achieve this result, we need a very clean metal surface, near perfection. Every metal has an oxide layer that needs to be removed before the commencement of cold welding. We will discuss this in more detail, but let us first understand the pros and cons of the process.
