Actually I always used rigaku miniflex for XRD measurement and get .ras, .asc, .raw file from that and what the best free software for want to know the materials containing on my compound
There are various softwares which you can use to identify your compound, those are FullProf, Jana2006, Maud, Match, X'pert high score plus, UnitCell, Powder, Origin, JCPDS and many more.