Tapping an artifact won't cause its abilities to stop applying unless those abilities say so.
Metallic Rebuke
If an artifact you control has a mana ability with {T} in the cost, activating that ability while casting a spell with improvise will result in the artifact being tapped when you pay the spell's costs. You won't be able to tap it again for improvise. Similarly, if you sacrifice an artifact to activate a mana ability while casting a spell with improvise, that artifact won't be on the battlefield when you pay the spell's costs, so you won't be able to tap it for improvise.
Improvise doesn't change a spell's mana cost or mana value.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Eric Deschamps
Card data via Scryfall. Rarix is fan-made; not endorsed by the rights holders.
