The work is aimed at the development of a new sintered aluminium alloy with a low temperature coefficient of linear expansion that opens fundamentally new opportunities for solving the modern needs of domestic machine-building and instrument-making enterprises in light materials with special physical properties. Phase composition, structure and properties of cast aluminium alloys Al–Si–Ni with different contents of silicon and nickel, as well as powders obtained by grinding rapidly-quenched metal ribbons of these alloys in a high-energy ball mill are studied using various methods of structural analysis. The obtained values of the coefficient of linear expansion of the studied alloys in the cast state are significantly lower than those of pure aluminium, and they amount to $\cong (11-15)\cdot 10^{-6} K^{-1}$. The method of obtaining a powder of a rapidly-crystallized alloy by manufacturing a rapidly-quenched metal ribbons using melt spinning followed by its dispersion in a high-energy ball mill is proposed for the fabrication of finely-dispersed powder and subsequent hot pressing.