# WHAT SHOULD BE CONSIDERED WHEN SELECTING THE APPROPRIATE TUNGSTEN FOR THE TIG PROCESS? When selecting the correct tungsten electrode for the TIG (Tungsten Inert Gas) welding process, the following factors must be taken into account: — ## 1. **Type of Current Used** – **DCEN (Direct Current Electrode Negative):** Pure tungsten or thoriated tungsten electrodes are recommended, as they withstand high heat concentrations at the weld pool. – **AC (Alternating Current):** Pure tungsten or zirconiated tungsten electrodes are preferred, since the alternating current causes the electrode tip to form a balled end, which helps stabilize the arc. – **DCEP (Direct Current Electrode Positive):** Rarely used in TIG welding due to excessive heat buildup at the electrode. — ## 2. **Type of Base Metal to Be Welded** – **Carbon steel and stainless steel:** Thoriated (EWTh-2) or ceriated (EWCe-2) tungsten electrodes are commonly used with

The first thing to do is identify the base material to be welded and which tungsten electrode options can be used for the welding application.

Remember that not all electrodes are suitable for all materials to be welded, as arc starting and arc stability can be affected.

Below are the most common tungsten types and their corresponding base materials.

(GREEN TIP) WP – PURE TUNGSTEN

It is the most widely used for welding with alternating current AC. It is used primarily for welding aluminum and magnesium.

 (GRAY TIP) WC20 – 2% CERIATED

It is suitable for welding applications with both alternating current and direct current DC AC, with excellent arc starting capability at low amperages. It is used for pipe welding and tank fabrication. It also performs excellently for welding small or delicate workpieces. It is not recommended for high-amperage applications.

(BLUE TIP) WL20 – 2% LANTHANATED

An excellent lanthanated tungsten electrode alternative. Also known as the stainless steel tungsten electrode. It is highly versatile for AC / DC and is recommended for carbon steel, stainless steel, nickel alloys, titanium, and aluminum.

 (RED TIP) WT20 – 2% THORIATED

This material is prohibited in many countries due to radiation emissions. This electrode offers excellent arc ignition even at low amperage and is widely used with DC for steel, stainless steel, nickel alloys, titanium, and copper. It is not recommended for use with alternating current AC for welding aluminum.

(PURPLE TIP) RARE EARTH

It produces a very stable arc and low heat at the tip, resulting in less wear and a longer service life than thoriated tungsten electrodes. It is excellent for welder productivity and safety. Additionally, it provides superior arc starting and performs excellently with both direct and alternating current, making it ideal for welding titanium, magnesium alloys, aluminum, copper, brass, carbon steels, and stainless steels.