Ferritic is just ferritic and aust is just well, eh, austenitic. Not much to explain. Take a look in one of the ASM books if you need further definition on that.
Huub
- You never get what you expect, you only get what you inspect.
Ferritic stainless steels have a body centered cubic crystal structure (except when martinstic) but they start out BCC and austenitic steels have a face centerd cubic crystal structure.
Refer the phase diagrams of Fe-C or Fe-Cr below, the "ferrite (alpha)" and "austenite (gamma)" are types of the material microstructure. It can be for the plain carbon steel or the stainless steel.
Austenite is a kind of metallurgical gentrification that happens when large numbers of nickel families invade a predominantly ferrite neighbourhood. At a critical population level they all say "we're not having this living arrangement anymore" and they start pushing the old iron residents around. They are powerful and it doesn't take many to cause a major transformation. The street grid is no longer square and the buildings start tilting. The cost of housing skyrockets.
Other visitors like the chromiums are much better behaved - they blend in, unlike nickel are happy to dance with others, and they even shield the hood from bad outside influences.
Hope that answers your question.
"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
