Studying for the CWI is a monumental task.
When you review the body of knowledge that the CWI exam is drawn from, it is massive and would take years to read every single word of it. AND much of it is beyond understanding for most of us mortal welders.
For quick advice, Wikipedia is your friend. If you read it's article on Austenite, it does not contain the word Austenitic, these are different terms, sorta kinda.
The Austenite phase of low carbon steel such as A36 does not exist at room temperatures, nonmagnetic, just like a blacksmith when quench and tempering will test a tools heat with a magnet before quenching.
Here's a short list of definitions you might find helpful.
http://www.toolingu.com/definition-500230-18105-austenite-phase.htmlAs is with so many terms in science and technology, most of these definitions contain words requiring further defining. Like trying to organize the hobby bench in the garage. Each item you clear off the shelf leads to organizing another tool box or shelf.......
Fun aint it? Gawd! I LOVE this stuff...