The Russian started enthusiastically and was letting fly with a string of rapid combinations.
Pehlivan was struggling to affect the contest and Ayrapetyan was firmly in the ascendancy.
The Turk came forward in the final round but walked onto a lot of Ayrapetyan's counter-punches.
The Russian's lead was four points at the start of the round and he stretched that advatage by forcing a standing count with a heavy blow.
Ayrapetyan controlled the bout from start to finish and he went on to clinch a 19-11 verdict.