Slide 5 of 12
What you are looking at in this slide is a representation of the 300 Series Stainless microstructure. The large ORANGE grains are the non magnetic element known as Austenite. The GREEN element is known as Ferrite and is the magnetic element. Ferrite is formed by choosing the correct chemistry and cooling rates. The ferrite is very important in preventing cracking. It can easily be measured by means of a Ferrite Gage. This measures the magnetic response of the overlay and corresponds to what is known as a Ferrite Number.