aka= also known as Example: That's John, aka Jonno.[ maybe his nick name] An "alias" is also a false name used to conceal one's identity; an assumed name: The police files indicate that “Smith” is an alias for Simpson.

Yes, they are interchangeable. There is no difference in the meaning. For those who don't know, AKA is an acronym for "Also Known As..." "Police are searching for Lewis Griggs, aka Lennie Green."