What did factory managers expect women to do when men returned home from the war?

A lot of them did return to their families, however the role of women in the factory was actually cemented in American and other cultures upon the war ending, so many women continued to work and even started careers. Cue second wave feminism.

Many women lost their jobs when men returned from the war. They were expected to go back to their normal duties of being a housewife and looking after the children.