Is the phrase "Be quiet, lest I divorce you" considered a divorce if it was said with the intention of threat, and the wife did not heed it until after it was repeated, and then she became silent?

This phrasing is a warning and a threat; it does not result in divorce, whether the wife remains silent or not. We advise you to stay away from threatening your wife with divorce, as it is an unsound approach and not one of the legitimate means for reforming a woman, and it causes her harm that contradicts living together in kindness. Ibn 'Uthaymeen, may Allah have mercy on him, pointed out that admonishing the wife is better than threatening her with divorce. The correct way is to admonish her and remind her of the verses of Allah, the Most High, the Most Glorious.