Can ''your'' and ''you are'' be use interchangeably in a sentence or better as synonyms?

NO , THEY ARE DIFFERENT IN GRAMMER NATURE , HAVE DIFFERENT USE,,,

Different words grammatically and in their meanings. Not interchangeable.

Agree with shagufta zafar

They are different .opposites are my and I'm

Completely different Nicholas as Shagufta has indicated."your" meaning "of you/belonging to you" and "you are"  describing "you" or some "characteristic" of you.

Both have different meanings. 'your' is a possessive pronoun whereas in 'you are' , you' is used as personal pronoun and it could be in subjective as well as objective case with 'are' as helpining verb or copula/linking verb. 

In spoken enlglish both could have the same sound when you are used in contraction e.c

your = yor      Is it yor pen?    you

you're = yor   Yor nice     you are

I agree that there is a difference