Creating the Structure and Properties of 7075 Alloy Casts by Thermal and Forming Processes

• Autorzy: Majerski Krzysztof , Dziubińska Anna , Winiarski Grzegorz , Szucki Michał , Drozdowski Krzysztof

Identyfikatory

DOI

10.12913/22998624/112361

• Języki publikacji: EN

Abstrakty

EN

In this paper, the hot formability of 7075 aluminum alloy sand and permanent casting ingots were verified. The experiment was carried out by using casting, heat treatment (homogenization) of ingots and conducting isothermal compression tests at temperatures of 420-500°C. The effect of the forming temperature on the microstructure, the tendency for crack formation and hardness were determined. The results show that ingots in the as-cast state have a dendritic network structure rich in the second phase precipitation on the grain boundaries. After the homogenization process, the microstructure is significantly more balanced. The forming process at 420-480°C of sand casts leads to significant grain elongation and crack formation, mainly at the grain boundaries. Raising the forming temperature to 480-500°C leads to a reduction in the occurrence of cracks. On the other hand, permanent mold castings do not reveal cracks during deformation in the temperature range 420-480°C.

Słowa kluczowe

EN

aluminum alloys; heat treatment; metal forming; microstructure

PL

stopy aluminium; obróbka cieplna; obróbka metali; mikrostruktura

• Wydawca: Lublin University of Technology ; Polish Society of Ecological Engineering (PTIE), Branch of PTIE in Lublin
• Czasopismo: Advances in Science and Technology. Research Journal
• Rocznik: 2019
• Tom: Vol. 13, no 4
• Strony: 15--21
• Opis fizyczny: Bibliogr. 21 poz., fig., tab.

Twórcy

autor

Majerski Krzysztof

• Lublin University of Technology, Faculty of Mechanical Engineering, ul. Nadbystrzycka 36, 20-618 Lublin, Poland

autor

Dziubińska Anna

• Lublin University of Technology, Faculty of Mechanical Engineering, ul. Nadbystrzycka 36, 20-618 Lublin, Poland

autor

Winiarski Grzegorz

• Lublin University of Technology, Faculty of Mechanical Engineering, ul. Nadbystrzycka 36, 20-618 Lublin, Poland

autor

Szucki Michał

• AGH University of Science and Technology in Cracow, Faculty of Foundry Engineering, ul. Reymonta 23, Building # D8, 30-059 Cracow, Poland

autor

Drozdowski Krzysztof

• ZOP Co. Ltd Forging Plant, ul. Kuźnicza 13, 21-045 Świdnik, Poland

Bibliografia

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Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).