The challenge of identifying materials

PMI Testing

Having an accurate idea of the grade of material you are dealing with is important. Small differences in grading can mean a big difference in things like the physical and mechanical properties. In turn that can affect things like what kind of maintenance you need to do. Format NDT Ltd support clients who need help identifying materials. We can step in to provide PMI testing if you don’t have a material certificate or want to test the validity of one.

Grading issues

The 20th century was an incredible time for metallurgy. It saw the creation of a huge array of new alloys to meet a growing number of requirements in different industries. This was exciting because it saw the creation of materials with lots of diverse characteristics.

While this growth was great news in terms of the progress, it did cause some issues. The biggest one was that it meant there were way too many different designations for materials. In fact, different schemes could have a separate designation for the same material. The end result was a lot of confusion.

In the 1970s the decision was made to improve the situation. This led to the creation of the unified numbering system (UNS). Today this is the most common way to identify materials in North American as well as various other parts of the world.

The categories

The UNS material code has a number of categories for different metals. For example, the A series is for aluminium and its alloys. Each designation here will begin with A followed by 5 numbers ranging from 00001 to 99999. Other metals with their own series include copper (C), cast irons (F), cast steels (J), stainless steels (S), zinc (Z), nickel (N), precious metals (P), and more.


The thing to keep in mind is that each designation represents a single metal or alloy. There is a huge catalogue that has information about all of them. Some also include details of the chemical composition. In addition, there may be info about specific mechanical or physical properties.

Choose us when you need PMI testing

Format NDT Ltd knows how useful it is to be able to say with certainty what kind of material you are dealing with. We can help our clients to do this. Our team have access to the latest material analyser technology. As a result it can quickly check a metal against the latest codes to provide an accurate ID.

So, if you have a metal or metal product to identify, don’t hesitate to ask us for PMI testing. We can visit your site to provide it or take items to our lab to test. We can even identify welding filler materials.