My understanding of a cannonball is that it’s a explosion-powered shot put, essentially a giant musket ball. They probably didn’t explode like bombs as portrayed in many movies.
However my intuition makes me think that they would kind of shatter on impact, just because of how fast they traveled.
Did cannonballs shatter, and if they do what would it have looked like?
Quite the opposite - in fact, round shot was counted on to keep going after the first hit. More can always be said on the matter if anyone would like to contribute further artillery knowledge; for the meantime, OP, here's a few previous posts for your attention: