Effect of austenizing temperature, aging temperature and duration, deformation degree on the change of strength, elasticity, relaxation resistance and magnetization of Fe-Ni-based steels (03N16K4M5T2Yu, ZI89-VI) and Fe-Cr-Ni-based steels (03Kh12N8K5M3TYu, ZI90-VI) produced by vacuum smelting is investigated as well as of slightly alloyed 03Kh14N8M2T steel produced by usual smelting. The application of steel free from Co and Mo is recommended for the case of operation of the maraging wire and the workpiece made of one at a temperature up to 300°C.