What Is Stainless Steel?
Stainless steel is an alloy consisting of iron and chromium that is sometimes combined with other metals such as nickel. It can be used for several different applications thanks to its unique fire, corrosion resistance, recyclability, durability and mechanical properties. This is why it is commonly found in everyday items and used in commercial applications across several industries including transport, medicine and logistics.
Steel consists of iron and carbon while stainless steel contains 11% to 13% of chromium, less than 1.2% carbon and other alloying elements. Elements can be added to stainless steel to improve certain properties depending on the application and project specifications. Stainless steel forms a chromium oxide layer when exposed to oxygen, which protects it from any damage.
Can You Weld Stainless Steel?
Many people wonder if they can weld stainless steel themselves. While the answer is yes, the process to weld stainless steel is not simple as it is very efficient at retaining heat, which makes the welding process much more complex and often requires a professional welder.
What Type Of Welding Is Suitable For Stainless Steel?
Stainless steel can be welded using different welding methods including shielded metal arc (MIG), gas tungsten arc welding (TIG) and spot welding depending on the specified outcome requirements.
TIG welding stands for Tungsten inert gas welding. TIG uses a non-consumable tungsten electrode to run a current through the metals that need to be joined and may also use a filler metal. It uses an electrical arc (DC or AC depending on the metal) to melt the steel and inert gas to prevent weld oxidisation. TIG welding is good for thinner metal pieces up to 5mm thick and is a technique sensitive welding process in terms of timing and controlling the torch.
TIG welding can be used for a variety of applications but is primarily used for pipeline and pipe welding. It is also commonly used in the aviation, aerospace and metal fabrication industries. TIG welding is more effective at welding thin and special materials such as titanium.
Spot welding is also known as resistance spot welding and is performed by welding 2 or more metal sheets together using pressure and heat that is generated from an electric current. It is commonly used to permanently attach 2 separate pieces of metal at specific points.
Spot welding is commonly used in a range of industries such as automotive, rail and construction. It is a fairly straightforward process, which makes it suitable for applications that requires a high volume of output.
MIG welding is an arc welding process that uses a continuous solid wire electrode that feeds into the weld being made and becomes the filler material that helps join the 2 metals together. It can be used to weld thicker materials (up to 40mm) and heavy-duty objects more efficiently when compared to TIG welding. As a result, MIG welding is often easier and less technique sensitive.
MIG welding is primarily used for production work (furniture and displays etc.) and industrial applications. It is better suited for applications that are smaller or have a lower volume of work.
What Is The Best Welding Method?
There is no straight answer to this question as this would highly depend on the application. To decide which welding method you should use, you need to consider the following:
- Welder’s skill level
- Desired aesthetic appearance
- Metal thickness
- Labour and machinery costs
MIG and spot welding is much more affordable and faster to complete while TIG welding works the best for thinner metals or items that require an aesthetic appeal.
How Difficult Is It Welding Stainless Steel?
Stainless steel retains heat much more efficiently than other metals and excessive welding heat can warp and even distort the stainless steel when it is cooling down. This can cause irreversible damage including marks and blemishes that cannot be repaired. The surface can also be scratched easily and precautions should be taken when handing stainless steel.
These are the different techniques that can be used to weld stainless steel. It is important to choose the right welding depending on the application use and production volume. Our team at Ogis Engineering is equipped to help you with your welding project. Contact us today to discuss your project.