Dana Trivigno opened the scoring for the U.S. at 11:42 of the first period and Darkangelo's goal put the visitors up 2-0. Emily Pfalzer assisted on both American goals.
Blayre Turnbull scored for Canada midway through the third period but the comeback attempt stopped there.
American goalie Alex Rigsby made 26 saves in the win, while Canada's Emerance Maschmeyer stopped 22 shots in the losing effort.
Earlier Thursday, Kristin O'Neill scored in the third period and Canada's U-18 women's team held on for a 3-2 win over the U.S.
Lindsay Agnew and Sarah Potomak scored second-period power-play goals for Canada. Marlene Boissonnault stopped 23 shots for the win.
Alyssa Gorecki and Rebecca Gilmore replied for the U.S. Brittany Bugalski made 28 saves.