Guide to Duplex Stainless Steel Welding

Published on 08 August 2023

5 min

Guide to Welding Duplex Stainless Steel

Harry Brearly, on August 13th, 1913 identified steel with 12.8% chromium and 0.24% carbon, regarded as the first ever stainless steel. Being an extremely versatile material, stainless steel has become commonplace and is being used across several industries.

What is Duplex Stainless Steel?

Among the many different types of Stainless Steel, one that especially stands out in the field of welding is Duplex Stainless Steel. The word Duplex sounds residential, but it is used here because Duplex Stainless Steel houses two-phase microstructures.
In simpler terms, it means that it has grains of 2 types of stainless steel: austenitic and ferritic. Duplex Stainless Steel predominantly shows properties of both Austenite and Iron, hence the interesting name. Within Duplex Stainless Steel grades there are sub-categories, the most common being Duplex Stainless Steel 2205. This widely used material is the most well-known for its high yield strength.

Some of the other properties of Duplex Stainless Steel are:

High Tensile Strength
Corrosion Resistance
Stress Corrosion Cracking Resistance
Resistance to pitting
Low-Maintenance
Environment friendly
Good Weldability

Among its many properties, the Duplex Stainless Steel Price also stands out for its affordability, especially as compared to other austenitic stainless steels.

Welding Duplex Stainless Steel

When it comes to the applicability and the history of welding, duplex stainless steel is making a mark. Being corrosion resistant, it is used in various industries, such as petrochemical, pharmaceutical, oil and gas, biomass, mining, and more.

While Duplex Steel 2205 has good weldability, the welding process can be different. The first and foremost thing to note is that all conventional welding methods, MMAW, GMAW, GTAW or TIG, SAW, and more, can be used.

What determines the welding method is the requirement of the project, welding positions, and productivity. Here is how different welding techniques can be used with Duplex Stainless Steel grades,

GTAW or TIG Welding

This should be ideally used for thinner materials and is commonly used on pipe joints. The FW 2209, is a solid wire for TIG welding by D&H Sécheron. This wire, under optimum welding conditions, will give a bright finish, stable arc, and will be spatter-free. Having duplex microstructures, it works best with duplex stainless steel welding electrodes.

MIG Welding

With Duplex Stainless Steel wire, MIG welding yields an excellent weld finish. While it is restricted to the horizontal welding position, the work environment it provides is good. The weld is also determined by the wire used, and one such wire by D&H Sécheron is the AUTOTHERME-2209 which is a stainless steel SAW wire designed for optimum performance.

D&H Sécheron also has choices within Duplex Stainless Steel Electrodes. Some of them are:

D&H 1414(NS): This welding electrode is widely applicable in petrochemical, oil and gas, and even the marine industry. The reason for this versatility is that it provides excellent operating characteristics for groove and fillet welding in the down-hand position.
D&H 2594(NS): A non-synthetic electrode, the D&H 2594(NS) exhibits high strength, high impact energy as well as resistance to pitting, stress corrosion cracking, and crevice corrosion. With such outputs, it is used in offshore platforms and mechanical & structural components.

Stainless steel welding has been in-style for the various reasons and features mentioned above. And knowing its wide applications, we’re sure it will remain so.
For any questions and queries about the best welding consumables, reach out to us!!!!

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