The type of precision welding which deals with micro parts in the fabrication industry is known as micro welding.
Here’s the deal:
While working with micro welding one must have very steady hands as it needs to make sure that other parts of the machine are untouched.
So what makes micro welding different from other types of welding? Well.
In this article, we are going to look at the process of micro welding, different types of it, what are its requirements, and other queries regarding it.
Let’s get started.
What is Micro Welding?
Micro Welding also sometimes called precision welding is the welding process used on small and delicate components, majorly in the electronics industry and drug & dairy industry.
The most commonly used process, Micro TIG welding, being an arc welding process creates very high temperatures that can go up to 5000 celsius.
Argon is utilized as a shielding gas, which guards the weld against environmental contaminants and replaces the air present with an inert environment, lowering the voltage requirements.
Unlike the typical TIG welding, micro welding is done at very low amperages i.e less than 5-10amps with a high power microscope at 20x.
The process sets up the weld by depositing fine yet very tiny blobs of the weld, producing weld beads as small as 0.005, and goes up to 0.065.
Each and every selection by the technician performing the weld of equipment to the welding wire should be carefully done.
Micro Welding can be classified into many different types such as Micro TIG, micro laser, micro resistance, etc which you will find later in this article.
Further, only some times of material are suitable for micro welding, since the material needs to be strong and long-lasting while maintaining the structural integrity of the machine.
Copper, phosphor bronze, nickel, stainless steel, molybdenum, tungsten, platinum, and titanium are considered the best materials for micro welding.
Used in almost every industry, micro welding cannot be replaced with other forms of welding and hence can be considered often unseen yet a very important requirement of every machine.
Types of Micro Welding
There are several different types of micro welding and each of them incorporates a different process and machine, explained below:
Micro TIG Welding
If you are an established welder you already might know what TIG welding is and the process behind it.
TIG Welding done at the micro-level, done via miniature TIG equipment is known as Micro TIG welding or micro-arc welding.
Used mainly for components with high alloy density, the micro TIG welding equipment is not much larger than a pen and offers high precision.
Similar to the regular TIG welding process, the Micro TIG process includes heating the filler material between the non-consumable tungsten electrode and the base metal. A well-maintained weld arc formation leads to the melting of metal which is then fused together.
However, it needs to be made sure that the heat does not damage the other parts surrounding the weld area. Since the process is very minute the chances of this happening are close to none.
Micro TIG welding is majorly used for rejoining damaged machinery parts together in the electronics industry that have high melting points. Also, Micro TIG is applied where dissimilar metals need to be welded.
Micro Laser Welding
As the name suggests, the micro welding process that incorporates laser is known as micro laser welding.
Lasers in the solid-state using light energy heat up the weld rapidly, melting the filler material. Due to its high penetration power, laser micro welding produces easy yet clean looking weld.
Laser welding is highly used especially for micro welding as it does not require electricity or pressure and hence doesn’t produce any gases during the process which may affect the weld negatively.
Although not required, micro laser welders still use shielding gas such as argon, helium, etc to tackle unforeseen weld continuities.
However, the technician working with micro laser welding must precisely do the job i.e since it does not involve electricity, using the laser might be tricky for some.
One must get a clean, straight shot over the base material and the filler rod via utilizing microscopic magnification similar to micro TIG.
Micro Laser Welding is a comparatively newer technology when compared to Micro TIG processes and some may find it difficult to adapt.
Micro Laser Welding is majorly used for thermoplastics which require deep clean weld, which is not quite achievable through traditional weld processes. Also, they are sometimes used for welding reactive metals.
Micro Spot Welding
Micro Spot Welding or micro resistance welding is used to join various metals through the heat generated from the resistance between the electrodes when an electric current passes through them.
Using the same principles of regular scale spot welding, but just done on a micro level.
Similar to other types of micro welding, this requires great precision as well. Accurate and consistent welding is required in order to weld at the micro level.
Micro Spot Welding is sometimes used over micro tig and micro laser welding as it is way more economical while also having low chances of damage to the weld.
Unlike the other two micro welding processes, micro spot welding is only used for some particular applications such as to make batteries, in the treatment of malpositioned teeth. Also, since micro spot welding can be automated via CNC or Robots they are commonly used in the automobile industry.
Micro Welding Requirements & Equipment
Since micro welding is only used for miniature parts, there are some standards set for micro welding equipment as well.
Micro Welding equipment can only be used with Materials with a thickness of less than 0.5 mm and having a cross-sectional area of 10 sq. mm. As already mentioned above, this is a very precise process and the weld beads made can be of 0.0065mm and go down as low as 0.005mm.
Being a very delicate process that can only be applied to certain instances, it is advised to have knowledge of all the welding processes and machines.
Further, while working with micro welding, micro tools are used too. Such as a miniature tool to properly place the filler metal via a magnifying microscope.
Each step should be taken cautiously, and the end results are based on these small steps since we are talking about micro here.
Micro welding can only be done with their designated machines, unlike the usual welding. For each of the processes, there are specific machines with certain features.
For MicroTIG Welding, Orion mPulse Micro TIG Welder (by sunstone welder is the complete package. Although there are several other options available as per your needs starting from $2,600 and going all the way up to $14,500.
I hope you were able to acquire the knowledge you were looking for about micro welding.
through this article.
Indeed, there is much more to learn. Remember just like any other form of welding, micro welding requires strict safety measures.
Also, if you are new at this, it would be better to consult a micro welder you know or give a contract to a micro welding company for your projects.