ISSN (print) 1995-2732
ISSN (online) 2412-9003

 

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Abstract

Aluminium-lithium alloys have a great potential in aero-space engineering. Enhancing the physical, mechanical and operational properties of these alloys by alloying provides an important problem. A high interest to these alloys can be explained by the fact that lithium with the density of 0.54 g/cm3 changes the modulus of elasticity of aluminium bringing it higher while reducing the weight of parts made from aluminium alloys. Rare earth metals (REM) added to aluminium alloys can enhance their strength, heat resistance and corrosion resistance. REMs produce a modifying effect leading to a more refined grain. Due to high reactivity of the components introduced in aluminium the production of aluminium-lithium alloys containing rare earth metals may pose certain challenges. Taking this into account, the vacuum resistance furnace of SNEV 1.3.1 / 16 with a helium atmosphere and the overpressure of 0.5 MPa was used to produce the alloys. An XRD analysis and a scanning electron microscope of the STEREOSCAN 440 series (England) were applied to study the alloys in view. A Vickers hardness tester (HV) was used to test the hardness of the alloys. The study confirmed that the addition of REMs can increase the hardness of the parent alloy to 170 HV. Cerium proved to be the most effective addition in terms of hardness and strength. The study of the microstructure of the alloys show that small additions of REMs can produce a modifying effect and result in a refined eutectic structure (α-Al + AlLi) in alloys. Along with eutectic crystallization, the precipitation of Al-REM intermetallic phases was observed in the alloys.

Keywords

Al+6%Li alloy, REM, Vickers microhardness, ultimate strength, microstructure, X-ray spectral analysis.

Shuhratjon A. Nazarov – Postgraduate Student

Academy of Sciences of the Republic of Tajikistan, Dushanbe, Tajikistan.

Izatullo N. Ganiev – D.Sc. (Chemistry), Professor

Academy of Sciences of the Republic of Tajikistan, Head of Laboratory at the Nikitin Institute of Chemistry, Du-shanbe, Tajikistan. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Nargis I. Ganieva – Senior Research Fellow

Nikitin Institute of Chemistry, Academy of Sciences of the Republic of Tajikistan, Dushanbe, Tajikistan.

Irene Calliari – Associate Professor

School of Engineering, Università degli Studi di Padova, Padua, Italy. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

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