Mechanical properties of Al-Si-Mg alloy castings as a function of structure refinement and porosity fraction

• Autorzy: Hajkowski M. , Bernat Ł. , Hajkowski J.
• Języki publikacji: EN

Abstrakty

EN

During design of the casting products technology, an important issue is a possibility of prediction of mechanical properties resulting from the course of the casting solidification process. Frequently there is a need for relations describing mechanical properties of silumin alloys as a function of phase refinement in a structure and a porosity fraction, and relations describing phase refinement in the structure and the porosity fraction as a function of solidification conditions. The study was conducted on castings of a 22 mm thick plate, made of EN AC-AlSi7Mg0,3 alloy in moulds: of quartz sand, of quartz sand with chill and in permanent moulds. On the basis of cooling curves, values of cooling rate in various casting parts were calculated. The paper also presents results of examination of distance between arms in dendrites of a solid solution \alfa (DASL), precipitations length of silicon in an eutectic (DlSi) and gas-shrinkage porosity (Por) as a function of cooling rate. Statistical relations of DASL, DlSi, Por as a function of cooling rate and statistical multiparameter dependencies describing mechanical properties (tensile strength, yield strength, elongation) of alloy as a function of DASL, DlSi and Por are also presented in the paper.

Słowa kluczowe

EN

mechanical properties; silumin; cooling rate; structure; porosity

PL

właściwości mechaniczne; silumin; szybkość chłodzenia; porowatość

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2012
• Tom: Vol. 12, iss. 4
• Strony: 57--64
• Opis fizyczny: Bibliogr. 18 poz., rys., tab., wykr.

Twórcy

autor

Hajkowski M.

autor

Bernat Ł.

autor

Hajkowski J.

• Division of Foundry, Institute of Materials Technology, Poznan University of Technology, Piotrowo Street 3, 60-965 Poznan, Poland,

Bibliografia

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