Ferrite is a solid solution of carbon dissolved in a Fe, which is commonly used as a symbol F.
The ferrite in stainless steel refers to the interstitial solid solution dissolved by carbon in a Fe, and its carbon dissolving ability is very small. It can only be dissolved into 0.0008% carbon at room temperature, and its maximum carbon dissolving capacity is 0.02% at 727 degrees centigrade. It still maintains the body centered cubic lattice. The commonly used symbol is F.
Due to the low carbon content of ferrite, the properties of the ferrite are similar to that of pure iron. The plasticity and toughness are very good, and the elongation is delta = 45% to 50%. The strength and hardness of low o b = 250MPa, HBS = 80.
The so-called ferritic stainless steel. It refers to the stainless steel which is mainly ferrite in the state of use. Its chromium content is 11%~30%, and has the structure of body centered cubic. As for the amount of iron in stainless steel, it has nothing to do with whether it is ferrite stainless steel. Ferritic stainless steel only depends on whether ferrite is used in the service state.
Ferrite has magnetic properties.
Austenite is a solid solution of carbon dissolved in gamma Fe, which is commonly used as a symbol A. It still maintains the surface centered cubic lattice of gamma Fe. Its carbon dissolving ability is larger. At 727 C, carbon dissolves to be Omega C = 0.77%, and soluble carbon is 2.11% at 1148. Austenite stainless steel tube is an organization that can be stable at a high temperature of 727 degrees C. The austenite is a good plastic, which is the organization required by most steel types at high temperature.
Austenite is not magnetic.