The 22 year old defeated Elly Ajowi Ochola in the quarter final at light heavyweight last night.
Duffy was awarded a unanimous 3-0 decision by the ringside judges and will be back in semi final action on Friday.
Joe Fitzpatrick and Sean Duffy are also assured of at least bronze medals in the lightweight and light welterweigh divisions after winning their quarter-finals at the SECC in Glasgow.
Five more Northern Irish fighters can secure bronze medals today.
South Africa's Siphiwe Lusizi is the opponent for Derry middleweight Connor Coyle.
Olympic medallist Michael Conlan takes on Ugandan bantamweight Bashir Nasir and Ballymena welterweight Steven Donnelly faces Custio Clayton of Canada
In the women's flyweight quarter finals, Michaela Walsh takes on Jamaica's Sarah Joy Rae.
While Belfast's Alanna Audley-Murphy takes on Dominican lightweight Valerian Spicer.