Ferrite levels in materials are important for many reasons. For austenitic SS, a small amount of ferrite will decrease the tendency for hot cracking during solidification. Too low of a number may indicate that there are hot cracks. Too high of a number may decrease the corrosion resistance. Duplex stainless steels are even more important to measure the ferrite. The reason is that the ferrite can vary over a wide range. Lower ferrite readings in duplex stainless steels can indicate a real potential problem. Improperly heat treated (insufficient cooling rate) duplex stainless steels can have sigma phase or other deleterious phases that can embrittle the material and cause catastrophic mechanical failures as well as the loss of the desired corrosion resistance. Our portable testers can give reliable and accurate readings on the level of ferrite in a sample.