Ray Bradbury had nothing to do with the creation of the Vulcans or anything related to Star Trek. You are confusing him with Gene Roddenberry. Vulcan philosophy is to a large extent inspired by Stoicism.
Vulcan Hephaestus is the Greek god of Blacksmiths.
Vulcan was actually the Roman god equivalent of Hephaestus.
Hephaestus
Hephaistos.
Hephaestus is the Greek name. In Roman, he was Vulcan.
His greek name was Hephaestus.
His greek name is Hephaestus.
Vulcan is the Roman name of a god that is called counterpart to Greek Hephaestus.
Hephaestus 'Ηφαιστος
Vulcan is the Roman god (Vulcanus), corresponding to Greek Hephaestus. Vulcan is also the Roman god of fire.
In Star Trek there is an alien called Vulcan. Spock is a Vulcan.
Hephaestus was the Greek name. The Roman equivalent was Vulcan.