S355 JR or J2 part 1

What steel should I choose? S355 JR or J2? Part 1

Well as always … it depends ? .

Let’s start with another question – why does #steel have such a classification? Why not use one steel type for all #structures? The answer is straightforward – yep – money!

Let’s compare prices of steel for typical applications:

S355JR – 100% of the price

S355J0 – 102% of the price

S355J2 – 107% of the price

The widely used steel EN10025-2 S355JR is not only the cheapest one, but it is also available out of the shelf for many section shapes. It is fine for most common applications, so it is easy to say “it is good enough” almost always.

“Almost” is the key word here.

Can steel used in Southern Italy be equally used in Northern Norway? Usually it cannot be and the reason for this is so-called Charpy Impact Test. It is testing the toughness of the material, or in other words, it is testing how much energy is needed to brake a steel bar at some certain temperature.

In the next post, we will try to expand on this topic and show how to assign steel grades, taking into account results from the Charpy test. You may be interested in the point, that for some cases #Eurocode can demand a maximum thickness of 40mm, while other publications allow using of even 200mm thickness plate for this same case!