He punched a fully grown technarch in the face and did damage. He's also durable enough to make shields to counter Galactus' 3 solar system apocalypse blast. In fact, Nova made a shield to protect Phyla and Peter Quill, but was on the outside of the shield.
So Nova took that blast and was well enough to pound on Quantum Annihilus. Until Annihilus basically killed him and Phyla had to step in.
But yeah, Nova stomps Iron Man.
World Mind could juts hack Tony's armour and make it explode tbh.
If I recall correctly the entire scene concerning Nova and his survival of the blast released from Galactus, toke place off panel. But somehow I highly doubt he tanked it Annihilus had to go back to some enter some form of cacoon to survive and he was wearing the Quantum Bands (ore whatever they are called).
The smoke cleared and Peter and Phyla were in a shield and Nova had energy sparking off him.
Annhihlus didn't enter a cacoon, he just took the blast. And it was implied he could've survived w/o The Quantum Bands.
' I think the Quantum Bands fueled you, and surviving Galactus drained you!'
That was after Annihilus had been using the Quantum bands to own Nova, and was fighting under his own power. As he wasn't drained wit h the Quantum Bands it seems he survived the blast w/o using the bands. Which although strange, in the scan where the blast hits Annihilus, he doesn't erect and kind of shield etc with the bands.
But either way, there's no way Iron Man would survive that blast, so even if Nova didn't take it, it's doesn't really matter in this fight.
Nova could end this in 3 seconds in a number of ways. He could just increase Tony's gravity to like, 400 X earths, pull him into the upper atmosphere then drop him, which leads to a broken Iron Man scattered across the USA.