Engineer Anatoly Onishchenko has developed a method to significantly reduce the mass of rotors, disks, and shafts of gas turbine engines. He proposed not making the part entirely from heavy heat-resistant alloy, but rather placing a lighter insert inside.

In the new scheme, a reduced model of the future disk or shaft is first installed in the center of the capsule. Then, it is covered on all sides with granules of heat-resistant alloy.

After hot isostatic pressing, a bimetallic blank is obtained, in which heavy metal surrounds a lighter core.

For a nickel alloy, the author suggests using an insert made of heat-resistant titanium, and for a titanium part, an aluminum alloy. Another option is graphite, whose density does not exceed 2 g/cm³.

From the editors of "Pervy Tekhnichesky": Onishchenko's method looks good on paper, but there are many questions.

Such a design still has the engineering problem of material compatibility. When choosing a light insert, it is necessary to consider differences in thermal expansion, strength, creep, and material behavior under cyclic loads. The presented patent does not contain the results of endurance tests of the finished rotor.

By the way, this is not the first idea from Onishchenko. Before this, he proposed a method for manufacturing a gas turbine engine blade forging using wood to reduce the weight of the part.