Fractographic Study of the Armor Steel of Self-Propelled Artillery Guns of the Red Army

摘要

The article presents a study of the fractures of steels which were used to make armor elements of SU-85 and SU-100 self-propelled artillery guns produced at Uralmash (UZTM) in 1943–1945 and are on display at the Museum of military equipment of the Ural Mining and Metallurgical Company (Verkhnyaya Pyshma, Sverdlovsk Region). In all the investigated samples of armored steel, an increased content of sulfur and phosphorus was found. It is shown that the fracture obtained at room temperature has a predominantly ductile transcrystalline character. The observed cleavage facets are associated with sulfide precipitates. The presence of oxide particles is not accompanied by local brittle fracture of the steel. Testing of the steel cooled in liquid nitrogen shows a decrease in the share of the ductile component in the fracture, but it does not lead to transcrystalline fracture.