<p>The features and patterns of variation of the nonequilibrium solubility of transition metals in aluminum in binary, ternary and more complex aluminum-based alloys are analyzed. The effect of multicomponent alloying is shown, in which the complication of the composition of the alloy by increasing the number of transition metals increases their nonequilibrium solubility in aluminum. It is established that the effect of the multicomponent alloying is implemented in the process of rapid crystallization (cooling rate 10³ – 10⁴ K/sec) and is caused by the increase in the crystallization rate due to intensification of the pre-crystallization supercooling.</p>