When it comes to aluminum TIG welding, the filler rod size is very important. What Rod Do I Use For Aluminum TIG Welding? And what size TIG filler rod you need will depend on what type of metal you are trying to weld. What color tungsten is best for aluminum? What type of gas should I use with my aluminum TIG welder when welding aluminum? These are all great questions that can be answered by reading this blog post!
So, what rod do I use for aluminum TIG welding? When you are welding aluminum, use pure tungsten or zirconiated tungsten electrode. Don't use a 2% thoriated tungsten electrode. Make sure that the diameter of the electrode is large enough to carry the welding current you want to use.
There are a lot of different rods for aluminum TIG welding. The 4043 aluminum TIG rod is used for 3003, 6061, and a355 aluminum castings. In general, it is the most versatile. If you have any castings with porosity issues, I recommend you use the 4047 filler rod--it has 12% silicon in it, which will make it flow better and fix those problems.
Related Post: Best Aluminum TIG Welder
# Table of Contents
TIG Welding Filler Rod Types
There are different types of aluminum filler rods that are made for certain jobs. 1XXX, 2XXX, 4XXX, and 5XXX are the families that make up these different types. Within these families, some alloys fit specific needs of welding jobs.
- 1XXX: Essentially Pure Aluminum Filler Alloys
- 2XXX: Aluminum Copper Filler Alloys
- 4XXX: Aluminum Silicon Filler Alloys
- 5XXX: Aluminum Magnesium Filler Alloys
01. 1XXX: Essentially Pure Aluminum Filler Alloys
In general, 1XXX aluminum alloys are very pure. They are good for applications that need to be conductive. None of these alloys crack easily. For example, you would use 1100 filler alloy if you were welding 1100 parent material.
Sometimes it can be hard or impossible to find an exact match. When this happens, you should use an alloy that is as pure as the parent material. For example, 1100 is 99% pure, and 1070 is 99% pure.
On the other hand, it is not a good idea to use filler metals 1XXX for welding materials that are not 1XXX. It is also bad to weld materials in different series together because the filler metal will take on some of the base alloys while welding, making it weaker.
Moreover, the 1XXX filler wires are very soft and hard to feed through. If you use a push/pull torch, then it is easier to weld with these wires.
02. 2XXX: Aluminum Copper Filler Alloys
2XXX is the only filler metal that we have available is 2319. It has copper and manganese, and titanium. It is good for welding aluminum armor with 2519 because it becomes stronger after being heated up and cooled down. Besides that, there isn't any other use for this filler metal.
03. 4XXX: Aluminum Silicon Filler Alloys
The 4XXX alloys are made of silicon and aluminum. The most common 4043 and 4047 alloys are simple 2 metal alloys. There are also 4643 and 4010, which have a little magnesium in them, so you can heat treat the welds to match the base metal better. This is important if you need to reheat-treat your welded assembly after welding it, such as with a solution heat treatment, quench, and age, because then the welder knows that the new weld will be able to take more heat.
Some alloys, such as R-A356.0 and R-A357.0, are used in foundries to make 3XX castings that match the chemistry of the weld with the alloy. They are used to fix castings before they are heat-treated so that there is no difference in chemistry between the weld and the casting.
However, the AlSi fillers are metals that do not crack when they are welded. They also don't crack very often. AlSi fillers also make sure that the metal doesn't get filled with holes like 5XXX fillers do.
Moreover, the 4XXX fillers are used to weld 6XXX metal. They can also be used to weld castings back together and themselves! In welding with 6XXX metals, the AlSi chemistry of the 4xxx metal helps prevent cracks from forming.
It is not good to use 4XXX filler to weld AlMg 5XXX alloys, such as 5083. When you put together the high Si content of the 4XXX with the high Mg in the 5XXX base material, it makes a tough, brittle substance. That means that your weld won't be strong and will have weak ductility and toughness. The only exception is welding 5052 using 4043 because 5052 has a low Mg content. So if you want to use 4XXX filler for any AlMg alloy, make sure it's 5052.
In conclusion, fillers in the 4XXX category are considerably more powerful than 1XXX fillers. They are also softer. For this reason, if you use them for welding with something like GMAW (Gas Metal Arc Welding), you might have to go slower because the filler rod will not stay in place well when feeding it. This means that push/pull guns and feeders are recommended but not always necessary when dealing with larger diameters.
04. 5XXX: Aluminum Magnesium Filler Alloys
A welder might want to know about 5XXX fillers. There are a lot of fillers out there, but the most common one is 5356. The higher the Mg content, the stronger the welds. Some other good ones also have manganese added to them to make them even stronger.
When you put filler in a weld, it might not be smooth. The 5XXX filler is less fluid than other kinds of filler. It also contains Mg, which leaves black marks behind when you use GMAW.
The 5XX and 4XX welding filler metals have different properties. Fillers like 4043 and 5356 are soft and make it easy for the welder to find a way to weld them together. The ductility of 4043 is between 6 and 10%, while that of 5356 is 25%. The shear strength of 5356 is about 50% higher than that of 4043.
The tensile strength of 5356 is greater than 4043. But usually, because the heat-affected zone (HAZ) of a groove weld is weak, not the weld itself.
5XXX alloys are used for three types of applications:
1) Joining 5XXX base materials to each other. In this application, use a filler alloy with slightly more Mg than the base alloy.
2) Welding low Mg content like 5052, 5154, and 5454 alloys using 5534 or 5754
3) Welding intermediate strength alloys like 5086 and 5083, with some people selecting 5183 for increased mechanical properties
Some jobs require these fillers. They are called 5XXX fillers and specifically 5356. You will often use them to weld 6XXX alloys like 6061 and 6063. These alloys must meet the requirements of mechanical properties.
On the other hand, welding aluminum can be tricky. To do it right, you need to use the right filler metal. When welding anodized aluminum, you should use a 5XXX or 6XXX filler metal. If you use a 4XXX filler metal, the weld will turn black, which won't look good.
Do not use filler 5XXX when welding 3XX casting alloys, such as A356 and A319. This is because these casting alloys contain silicon, and magnesium silicide will be formed if you do.
TIG Aluminum Filler Rod Chart


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Can you TIG weld aluminum without a filler rod?
Yes, you can weld aluminum without a filler rod. This is an intermediate drill and should not be attempted by beginners or those that have never TIG welded before. You would need any TIG welder that can produce about 100 amps DCEN.
After you learn about welding, it's time to start practicing. You can do this by learning the basics of TIG welding and practicing without using any filler metal.
The first skill drill is just TIG welding without any filler metal. We will learn how to do this with a TIG welder that can produce 100 amps DCEN.
There are many different types of TIG welders, but I will list some basic ones because I don't know which one you have.
The simplest type is a stick welder with a TIG torch connected to the negative cable and an argon cylinder attached to it. This setup is called dry, or scratch start because it does not use water for shielding gas like other welders that are set up.
A better setup would be a TIG machine with a lift arc. Lift arc is easier to start than TIG with no arc.
Next up the ladder, there is a TIG with lift arc and amperage control that you can end TIG while still shielding the puddle.
If you want to learn this skill, it might be best to use a foot pedal control because it is easier than using an electrode's torch switch option at predetermined amperages for several beads before introducing foot pedal amperage control.
You can use a torch switch to control the amperage of the machine. It would help if you focused on making an egg-shaped puddle, some electrode angles, some arc lengths, and some travel speeds.
The puddle size should be around 1/4″ or 6mm, and it should be kind of egg-shaped or semi-round.
Conclusion
When you want to get a good weld, you need to know what kind of rod to use. You need to know what the object is made out of and if it is aluminum or steel. If it is aluminum, you will use T4 rods because they are easier for it. But don't forget that different rods do different things like make the weld come out stronger or melt better in certain situations.
Last Updated on December 1, 2021 by weldinghubs