Improvement of Al-Si Alloy Fatigue Strength by Means of Refining and Modification

• Autorzy: Tupaj M. , Orłowicz A. W. , Trytek A. , Mróz M.

Identyfikatory

DOI

10.24425/afe.2019.129631

• Języki publikacji: EN

Abstrakty

EN

The paper presents results of a study concerning an AlSi7Mg alloy and the effect of subjecting the liquid metal to four different processes: conventional refining with hexachloroethane; the same refining followed by modification with titanium, boron, and sodium; refining by purging with argon carried out in parallel with modification with titanium and boron salts and strontium; and parallel refining with argon and modification with titanium, boron, and sodium salts. The effect of these four processes on compactness of the material, parameters of microstructure, and fatigue strength of AlSi7Mg alloy after heat treatment. It has been found that the highest compactness (the lowest porosity ratio value) and the most favorable values of the examined parameters of microstructure were demonstrated by the alloy obtained with the use of the process including parallel purging with argon and modification with salts of titanium, boron, and sodium. It has been found that in the fatigue cracking process observed in all the four variants of the liquid metal treatment, the crucial role in initiation of fatigue cracks was played by porosity. Application of the process consisting in refining by purging with argon parallel to modification with Ti, B, and Na salts allowed to refine the microstructure and reduce significantly porosity of the alloy extending thus the time of initiation and propagation of fatigue cracks. The ultimate effect consisted in a distinct increase of the fatigue limit value.

Słowa kluczowe

EN

Al-Si alloy; fatigue limit; refining; modification

PL

stop Al-Si; granica zmęczenia; rafinacja; modyfikacja

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2019
• Tom: iss. 4
• Strony: 61--66
• Opis fizyczny: Bibliogr. 26 poz., rys., tab., wykr.

Twórcy

autor

Tupaj M.

• Rzeszow University of Technology, Rzeszów, Poland

autor

Orłowicz A. W.

• Rzeszow University of Technology, Rzeszów, Poland

autor

Trytek A.

• Rzeszow University of Technology, Rzeszów, Poland

autor

Mróz M.

• Rzeszow University of Technology, Rzeszów, Poland

Bibliografia

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Uwagi

PL

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