The favourite South Korea had claimed the last three gold medals in the earlier rounds, with Im Dong-Hyun breaking his own world record.
The US team—Brady Ellison, Jake Kaminski and Jacob Wukie—stunned the opponents in the final three ends.
The US headed to Saturday’s gold medal match for the first time since 1996, and will face Italy in the semi-finals.
Saturday’s competition features an elimination round, along with quarterfinals, semifinals and the two medal bouts.
Earlier, South Korea won its quarterfinal match against the Ukraine, who had beaten the British trio.
Meanwhile, Italy beat China in the quarter-finals.