Тонкостінний виливок з високоміцного сплаву як одне з головних завдань ливарного виробництва: Processy litʹâ, 2020, Tom 141, №3, p.47-55

• Date: 2020
• Main Authors: Дорошенко, В. C., Калюжний, П. Б.
• Format: Article
• Language: Ukrainian
• Published: National Academy of Sciences of Ukraine, Physical-Technological Institute of Metals and Alloys of NAS of Ukraine 2020
• Subjects: тонкостінні виливки; високоміцні сплави; ступінчате охолодження; механічні властивості; лиття за моделями; що газифікуються
• Online Access: https://plit-periodical.org.ua/index.php/plit/article/view/93
• Journal Title: Casting Processes

Received 28.05.2020 UDC 669.13 (03) The current trend to reduce the metal content of products can be satisfied through the use of spatial castings of thin-wall shell and/or cellular structure. Such castings can be obtained by lost-foam casting, in which the foundry pattern interacts with two fluid media - metal, which is poured and replaces the pattern from the inside, and a mobile sandy medium that surrounds the pattern during molding from the outside. In addition, to obtain a thin wall in the castings of light weight allows the use of high-strength alloys that can be obtained using methods of structure control, including step cooling. Due to the latter in cast iron and steel products it is possible to obtain a multiphase structure with metastable residual austenite, which under load on the casting undergoes deformation martensitic transformation, thus strengthening the alloy. The use of dry unbound sand in the lostfoam casting allows for rapid knocking out of the hot casting mold, and use this sand as a medium for isothermal holding of the casting under step cooling by isothermal hardening. In contrast to steel and cast iron castings, where the increase of mechanical properties is achieved by processes similar to heat treatment, in aluminum parts the increase of mechanical characteristics is possible with rapid cooling of the casting by ablation casting. The essence of this method is to erode of the mold by water jets during hardening of the casting, while water, in contact with the surface of the casting, creates conditions for intensive cooling of the alloy and, as a consequence, the formation of fine-grained structure. In this way, thin-wall castings of complex configuration are obtained, using both cast and deformable aluminum alloys as the material. The technologies considered in the article contribute to the development of lightweight thin-wall castings from high-strength alloys with improved performance properties.