Physicists at the Ural Federal University (UrFU) have created a theory for the solidification of iron-nickel (Fe-Ni) alloy (invar). They determined that an important role in the technology of creating invar products, namely in the solidification process, is played by the oncoming flow: when an alloy cools, the liquid layer flows on top of the solidified layer. If this process is regulated, it is possible to control the characteristics of the alloys, obtain a more uniform structure, and improve the properties of the final product.