Welding occurs at wildly different temperatures, ranging from room temperatures to insanely hot temperatures. Knowing the specific temperature at which you’re welding doesn’t offer many benefits, but it’s a fun fact. But have you ever wondered what welding procedure requires the highest temperature?
The welding procedure with the highest temperature is laser beam welding reaching temperatures of around 3,000 degrees Celsius. For welding techniques that you’re likely to use every day, gas metal arc welding might be what you’re looking for, but it also doesn’t always reach maximum temperature.
In this article, you’ll learn some of the hottest welding techniques and the specific temperatures at which they are performed. Also, you’ll learn why some welding procedures require more heat than others and the main advantages of very hot welding techniques over the not-so-hot ones.
Why Does Welding Require High Temperatures?
If you have any substantial experience with welding, you should already know the process of preheating. Preheating refers to the process of raising the temperature of the area you’re welding before joining the metals.
While you’ve preheated metals throughout your entire career, have you ever sat to think about why this procedure is important?
Heating a metal before joining them with any welding procedure will remove the moisture, slowing the weld cooling rate. This reduces the likelihood of the weld cracking soon after you’ve completed the job.
While a higher preheat temperature may have benefits, the correlation doesn’t always apply. There are instances when the exposure of metal to extremely high temperatures can cause damage before the weld.
Depending on the strength and the durability of the metals you’re joining, the preheat temperature should also vary. However, there is a maximum preheat temperature that you should never exceed if you’re looking to get a usable weld.
In the next sections, you’ll learn the maximum preheat temperature for a weld. Also, you’ll learn how to determine the best preheat temperature for your weld using some easy steps.
What Is the Highest Temperature a Weld Is Performed At?
There are different welding procedures, and each of these welding procedures has different temperatures. Ranging from gas welding up to laser beam welding, all of these procedures are untouchably hot, but some are much hotter than others.
The welding technique that requires the highest temperature is laser beam welding. This technique involves joining metals using super-hot laser beams which allows for insanely precise and deep welds.
During a laser beam welding procedure, any material in the path of the laser beams melts and vaporizes instantly. The beam forms cavities that are filled with insanely hot metal vapors, allowing for other metals to join efficiently.
Laser beam welding outputs so much heat that the heat must be removed by conduction in real-time during the welding procedure. The temperature of a typical laser beam during weld can exceed 30,000 degrees Celsius in some cases.
While laser beam welding might be the hottest, it is only applicable for small materials. Since the laser beam is small and incredibly precise, it’s pretty tasking to create cavities large enough to join large metals. In that case, alternative welding techniques must be employed.
Another insanely hot welding procedure that works for larger metals is plasma arc welding. The temperature in a typical plasma arc weld can range from 15,000 to 30,000 degrees Celsius, with very hot ones touching 50,000 degrees in some cases.
It works similarly to tungsten arc welding, but only at a significantly higher temperature. In plasma arc welding, a copper nozzle shoots some of the super-hot plasma at sonic speeds, forcefully joining the metals upon contact.
Plasma arc welding is capable of cutting and welding precisely on almost all kinds of metals. Since it doesn’t have the same restrictions as laser beam welding, it has seen more widespread adoption in the welding industry.
Electron beam welding is another technique that requires high temperatures to join metals. It is famed for its precision, and that precision stems from the fact that it allows you to work with beams, just like in laser beam welding.
Unlike plasma arc welding, electron beam welding doesn’t compete with conventional welding techniques. Also, it doesn’t create cavities like laser beam welding; instead, the electron beams melt and bond metals on contact due to their kinetic energy.
Due to its similarities to laser beam welding, plasma arc welding can also reach the same temperature as laser beam welding. However, it’s more applicable than laser beams in circumstances where you need lower temperatures for softer metals.
If you want a mainstream welding procedure with the highest temperature, look no further than shielded metal arc welding. While it doesn’t reach the insane temperatures that counterparts like laser and electron beam welding reach, it also gets pretty hot.
Typically, shielded metal arc welding can reach and exceed 6,000 degrees Celsius. For context, this is about the same temperature as the surface of the sun, which makes it pretty hot.
In shielded metal arc welding, the work surface melts with a rod coated with electrode flux to create a weld. The insanely high temperatures are necessary for this metal rod and the work surface to melt together, making it a pretty hot technique.
Importance of Increasing the Temperature of a Metal before Welding
Preheating is an important part of welding. It is usually required, even if you’re using the hottest welding technique out there. Since you’ll be heating the metal anyway, you may wonder why you even need to raise the temperature of the metal for a few degrees before the weld.
However, heating the metals before commencing any welding procedure will guarantee a more controlled cooling, reducing the possibility of cracks. The presence of hydrogen in metals can also lead to cracks during cooling, and preheating a metal removes that too.
Preheating also removes the contaminants from metal before welding. Contaminants may cause many disadvantages, some of which may include unwanted cracks after the weld.
