Broken Iron Sword Handle/Blade, and similar broken weapon bits are listed as junk in the strategy guide, right alongside bowls and plates.
So, in all likelihood, it's completely useless. I thought the same thing when I found that in the tomb...kind of disappointed, really. Would've been neat to reforge it as some kind of epic Sword of the North.
Edit: Upon further inspecting the guide to double check this info, I also came across an item labeled "Ysgramor's Soup Spoon." Make of that what you will.
The soup spoon is a joke item inside Calixto's Curiosities shop in Windhelm. It resembles a fork and the shopkeeper will talk about it (as well as a few other, ahem, "artifacts") if you decide to take the tour. I did not know his tomb was in the game so definitely a cool find.