Is the superego a social component of our personality?
Yes, it is indeed the social component of one's personality
One's superego can be modeled and developed through observation of one's environment. The ethics & morals, that is practiced by your community or society, which you had been exposed to as you grow up. Would also be the foundation of your SuperEgo standards. The SuperEgo requires Social interaction and learning. The more interaction you have, the more developed your SuperEgo becomes. But the SuperEgo standards of morality will also depend on the standard of morality taht you had observed. So if you had screwed up standards of Morals & Ethics, you would likely have a screwed up SuperEgo.