Are you using an austenitic or duplex stainless steel?

Ferrite Testing

While many people think of stainless steel in broad terms, there are actually many different types. They can have some big differences in terms of their properties and uses. With that in mind it is important to choose the right one for each job. Even then it may be necessary to test the alloy before use. Ferrite testing in particular may be useful for determining how much of this there is.

Austenitic stainless steel

In terms of use, these are the most popular types of stainless steel. There are a number of notable grades here, including the 300 series (especially 304) and the 200 series. The first of these is a mix of iron, chromium and nickel. The latter has these elements plus manganese and nitrogen.

The thing to keep in mind with these types of stainless steel is they are relatively simple alloys. As a result they are generally either 100% austenite or a high percentage of it with some ferrite. For example grade 304 can have as little as 8% ferrite. The percentage all depends on things like the amount of ferrite formers in the alloy and the type of production.

Duplex stainless steel

While these are not as popular as austenitic grades, they are better for a number of applications. This is because they have higher strength and more resistance to stress and corrosion cracking.

The reason these steels are so different is they have microstructures that combine austenite and ferrite. This is where they get the name duplex. In these grades the amount of ferrite can be anywhere from a low of 20% to a maximum of 70%. This higher content is why they are stronger steels but also makes them slightly harder to work with.

Expert ferrite testing

Format NDT Ltd supports clients in various industries that use different grades of stainless steel. Our team can provide useful testing solutions that can give a more accurate idea of how much ferrite is in the metals. This can then indicate if there will be potential issues with working with them.

So, if you need ferrite testing, you can contact us. We can provide it on site at your facility or take materials to our lab if necessary. Whatever option you choose, we use the best equipment to give you the details you need.