No, 3 Aces form a Three-Of-A-Kind at the Showdown which is lower than a Straight. 3 Aces would beat any two pair or lower Three-Of-A-Kind like 3 Kings. Three-Of-A-Kind is a strong hand in Holdem if there are no four cards of the same suits or four connecting cards on the board – it’s quite likely to win with this hand at the Showdown.