The pair will stay in Belgium until January.
"I think that the deal has been signed off and both flew out on Thursday morning," Joyce confirmed to MUTV. "It will be a tremendous experience for them having continental football at club with high demands to get promotion.
"They're going into a pressure-cooker atmosphere with fantastic fans and hopefully they can play a part in it being a successful season.
"You've seen the benefits in the past for the likes of Jonny Evans, Fraizer Campbell, Danny Simpson, Ryan Shawcross, Lee Martin, Phil Bardsley, Sylvan Ebanks-Blake and Craig Cathcart. They're just a short few years ago and you can see what it can do for them being out there.
"Hopefully, they can enjoy their time out there and develop and improve as players."