Does ERW increase toughness?

We specialise in ERW tube because electric resistance welding has so many advantages. For example, it is quick and can have a high production rate. It also means there is no need for filler material so the tubing can have consistent properties. This results in better tubes.

There was new research in 2021 that looked at whether ERW could enhance the toughness of steel. We want to have a quick look at this today so we can see what benefits it could offer to end users.

What is toughness?

Before we start, we want to look at three key terms that some people often confuse. They are toughness, strength, and hardness. The trio are not interchangeable. In fact, they are three completely different characteristics. To make it clearer, they mean:

  • Toughness – the ability to absorb shocks before fracturing
  • Strength – the ability to resist deformation
  • Hardness – the ability to stand against friction and resist scratching

How does ERW help?

ERW tubeElectric resistance welding is a really interesting technique. Unlike many others it does not create a large heat affected zone. Instead, it is relatively small at the edges. There is also a rapid cooling process once the weld is finished.

The crucial thing to remember here is the cooling after welding. What this does is create hard, brittle phases. They are vital to determining the toughness.

With ERW, the rapid cooling means the brittle phases happen in greater numbers. It results in a microstructure that is finer, with smaller grains. As a result, the final product would have higher toughness.

The research goes on to claim that an even higher cooling rate would go further. It would result in harder phases forming, improving the mechanical characteristics.

Impressively, the research claims that improving the hardness could make products like ERW tube far better. It would mean they could be useful for more applications, including many that were previously only suitable for seamless tubing. In turn that would offer some big cost advantages.

Heat treatment can also help here. The right combination of temperature and cooling rate alters key things like precipitate properties, the features of the phases, and particle size and distribution.

Do you want high quality ERW tube for your next project?

Union Steel Tubes knows how to produce quality tubing. We focus on getting it right, taking care to choose quality raw materials, adapt them carefully and weld using the best equipment. We also have quality controls in place and test to make sure everything meets our standards. As an ISO 9001 company, you can rely on us.

So, if you want ERW tube, speak to us. You can let us know what kind of application you have in mind and we can suggest tubing. We can even help you to look at potential issues and ensure you will be using sufficient tubes.