Adamantium. Arguably the toughest metal in the Marvel universe. It has shrugged off Hulk punches and bludgeons from Thor's hammer. The question I pose however is, would Superman be able to break/dent it? He can after all, do [url=http://media.comicvine.com/uploads/6/67064/2081435-supermansuper_strength_super.jpg]this.[/url] (Not even his greatest strength feat)
I'd imagine it would be like one of those unstoppable forces meets and immovable object kind of thing.
EDIT: No sundips and no punches that involve flight or speed. Just a regular ass standing on the ground punch.
EDIT 2: Changed from Vibranium to Adamantium because Adamantium evidently seems more durable.
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Considering that the comic book industry has basically made him out as God with a weakness to plot devices? -blam!-, the image you linked is basically proving that the writers are engaged in a giant -blam!-ed up game of one up manship. To answer your original question: Yes. Should is another question. And should he? No. Dent a couple inches of steel? Yes.