The short answer
No. The Army Service Ribbon is a ribbon-only award. It has no matching medal, and it is worn on the uniform as a ribbon. It is awarded for completing initial entry training.
What the Army Service Ribbon is
The Army Service Ribbon recognizes the completion of initial entry training. For enlisted soldiers, that generally means Basic Training and the Advanced Individual Training that follows for many occupations. Because it is a ribbon, it is worn in ribbon form and is not presented as a full-size medal.
Who receives it
Soldiers who complete initial entry training generally receive the Army Service Ribbon. The eligibility rules are set in Army regulation and have changed over time, so check the current rules for the period in question before deciding whether a particular soldier should have one.
Other ribbon-only awards
Several other US Army awards are ribbon-only. The Overseas Service Ribbon and the NCO Professional Development Ribbon are two common examples. Both are worn as ribbons, and neither has a matching medal.
Why people think it has a medal
Ribbons look like the ribbons of medals, and many people use “medal” for any award. Some awards do come with both a ribbon and a medal, which blurs the distinction. The Armed Forces Reserve Medal, for example, is a medal with a ribbon, so it is easy to mix up with a ribbon-only award.
How to recognize one
Look for a single ribbon or a ribbon bar, with no medal attached. If a ribbon has no medal beside it, it is probably a ribbon-only award. Ribbons on a uniform are arranged in a set order, and the Army Service Ribbon sits among the service ribbons in that order. Check the order against the uniform regulation before drawing conclusions about a bar.
Confirming an award
For a specific soldier, the service record is the best source. Request it from the National Personnel Records Center using Standard Form 180, and check the awards listed in the record.