If you're asking that the words are interchangeable, then no. I often get Americans gleefully telling me that 'mate'='sexual partner', though such a meaning isn't commonly recognised in UK/Australia. To us, it roughly means 'friend'.
In Australia, we do pepper "mate" all through our speech similar to how Americans use "man". It can be quite funny how often we use "mate"! In this usage, the word kind-of functions as a sentence marker, tucked between phrases. It still includes the listener in the story and holds onto their attention. It's also probably more a habit than anything else, so if you were planning to use "man/mate" in speech, you need to listen to a lot of native speakers first to get an idea of how often and when to use it.
Surprisingly, this habit also happens in a lot of the ancient Greek texts - phrases such as "man, be happy!" and "man, I understand what you're saying" often turn up in translation. So the habit is by no means new in language.