"Men are the protectors and maintainers of women, because Allah has given the one more strength than the other, and because they support them from their means. Therefore the righteous women are devoutly obedient and guard in the husband's absence what Allah would have them to guard. As to those women on whose part you fear disloyalty and ill-conduct, admonish them (first), (next), refuse to share their beds, (and last) beat them (lightly); but if they return to obedience, seek not against them means (of annoyance); for Allah is most High and Great (above you all). If you fear a breach between them twain, appoint (two) arbiters, one from his family and the other from hers. If they wish for peace, Allah will cause their reconciliation; for Allah has full knowledge and is acquainted with all things." (An-Nisa': 34-35)

Thats what the quran says, beating (slap on face is not allowed) can be used as last option to avoid divorce.