By means of the materials science methods, the effect of additional Au layers with a low surface energy (of $\cong$ 1.5 J/m$^2$) in [Fe$_{50}$Pt$_{50}$(15 nm)/Au(7.5 nm)/Fe$_{50}$Pt$_{50}$(15 nm)]$_n$ film compositions (where $n$ = 1, 2) obtained by the magnetron sputtering on SiO$_2$(100 nm)/Si(001) substrates on processes of thermally activated ordered $L1_0$-phase formation at annealing in vacuum is studied. As established, the disordered $A1$-FePt phase is formed in Fe$_{50}$Pt$_{50}$ (15 nm) layer in film compositions at deposition on substrates at room temperature. Both the ordering process and the ordered $L1_0$-FePt phase formation in films depend on level of compressive mechanical stresses in Fe$_{50}$Pt$_{50}$ (15 nm) layer. Increasing in intermediate Au layer number and total thickness of film composition in three times decreases of compressive-stresses’ level that leads to slowing-down of ordering processes, increasing in start ordering temperature from 650°C to 800°C, reducing in coercive force, and inhibiting of (001) texture with easy-magnetization axis location perpendicularly to film surface.