Why Are My TIG Welds GREY?

Why does my TIG electrode melt?

TIG electrodes melt due to a variety of reasons, the most common are: diameter of the electrode too small for set current, the polarity of the torch is clamped electrode positive, welding with DC instead of AC or the electrode material is not suitable for the welding setup..

How do you get rid of heat discoloration on stainless steel?

Dip a soft cloth in vinegar and rub over the surface of the stainless steel. The heat streaks should start to rub off of the metal and transfer onto the cloth. Continue to rub the surface of the steel vigorously until no more streaks come off of the surface.

Why is my Tungsten turning black?

If the tungsten electrode turns from its normal color of light gray to a shade of purple or black, that is an indication to increase post-flow time even more. In addition to causing various weld puddle troubles, contaminated tungsten electrode is also the leading cause of an unstable arc.

What are the disadvantages of TIG welding?

Disadvantages Of TIG: It will take a lot of time when welding. Welding with this welding machine is time consuming and the speed is slower than any other welding machines available in the market as well. It also has got lower filler deposition rate as well. It has got high initial cost.

Why are my stainless steel welds black?

What’s the reason for black welds when welding stainless steel? … It means that the weld is being exposed to oxygen from the air while it is still hot. This could be caused by : using too much current.

Is TIG electrode positive or negative?

DC TIG Welding is carried out with the torch negative and the work positive. That is also known as DCEN (DC electrode negative) or “straight” polarity for those with older welders. About two thirds of the heat goes to the positive side or the arc. For TIG the negative torch helps avoid overheating the tungsten.

Why do welds turn blue?

On stainless steel, for example, any color in the weld or HAZ shows that an oxide layer has formed, which can affect corrosion resistance. The darker the color is, the thicker the oxidization. The colors follow a predictable pattern, from chrome to straw to gold to blue to purple. … Corrosion resistance.

What color tungsten is for stainless steel?

Ceriated (Color Code: Orange) Like thorium, it is best used to weld carbon steel, stainless steel, nickel alloys, and titanium, and in some cases it can replace 2 percent thoriated electrodes. Ceriated tungsten has slightly different electrical characteristics than thorium, but most welders can’t tell the difference.

Why are my stainless TIG welds GREY?

Response from weldingtipsandtricks on stainless steel welds. Discoloration is oxidation. It is just a matter of the argon shielding envelope leaving the hot metal before it has a chance to cool enough to not oxidize. … Stainless has a tendency to bond really well with low heat as long as it is clean.

Do you TIG weld aluminum on AC or DC?

When TIG welding aluminum, alternating current (or “AC”) is almost always used. Alternating current has a scrubbing effect on the surface, breaking up oxides that limit weld quality. However, it is possible to TIG weld aluminum with direct current (also called “DC”).

Why do my TIG welds look dirty?

1. Poor gas coverage leads to contamination. The weld here shows contamination caused by lack of shielding gas, which can happen when the shielding gas is not turned on, there is either too little or too much gas shielding, or the gas is blown away.

Is TIG welding DC or AC?

TIG welding can be done with both, alternating current (AC) or direct current (DC). The type of current to choose depends on the workpiece material. Generally, Steel would be welded with DC and Aluminium with AC.

Why are my TIG welds black?

Brown or black oxidation or flakes in the weld puddle can be eliminated with increased EP. Too much EP, conversely, balls the tungsten and causes excessive etching. – Only start welding once the puddle has a shiny appearance. This is how you know the oxide is removed and you are ready to add filler metal.

What causes pinholes in TIG welds?

Paint, oil, grease, and rust can all cause pinholes to form in the weld bead. This is particularly important in TIG welding. The electrode and rods used for TIG welding don’t have any flux to clean a weld or handle impurities. You must get everything clean before you crack an arc.

Can you TIG weld without gas?

This method of welding requires every piece of the process to be VERY clean and 100% Argon is required as a shielding gas. … Without a shielding gas you will burn the Tungsten, contaminate the weld, and won’t get any penetration into the work piece.

Why are my aluminum TIG welds GREY?

A TIG weld that looks gray may be a result of surface oxidation. Tungsten inert gas (TIG) welding is often used to meet strict aesthetic, structural or code requirements. The TIG process is complex, and it is the most difficult process to learn.

Do you TIG weld stainless on AC or DC?

For TIG welding stainless steel, you can use a DC-only machine or AC/DC TIG welding machines in DC-mode. Importantly, make sure your machine has sufficient power to weld stainless steel.

Why are my aluminum welds black?

A: The black soot actually is magnesium oxide. … When magnesium is vaporized by the arc’s heat and comes in contact with oxides, black soot forms. A proper gun push angle of approximately 15 degrees helps keep gas coverage at the leading edge of the weld pool, which reduces soot.

Why does stainless turn black?

Stainless steel turning black is an oxidation process called rouging, and can be caused by many factors: exposure to oxidizers, contact with non stainless steel metals, or exposure to high heat.