Effect of Al-Y-Ce-La master alloy on structure formation, liquation processes and properties of AK7ch silumine (AL9)

Aleksei V Goncharov,Khosen Ri,Ernst Kh Ri,S Bratan

doi:10.1051/matecconf/201929800056

Abstract

The regularities of changes in the composition and properties (micro- and nanohardness, HB hardness) of the structural components - α-solid solution and eutectic components of the AK7ch alloy (AL9) depending on the value of the addition of Al-Y-Ce-La master alloy are established. With an increase in the addition of Al-Y-Ce-La master alloy a sharp change is observed in the composition and properties of the structural components of the AK7ch alloy - α-solid solution Si in aluminum and eutectic α + Si, as well as complex-doped aluminides from Si, Fe and rear earth metals (REM). The structural components of the AK7ch alloy are identified with the addition of an increasing amount of Al-Y-Ce-La master alloy (α-solid solution of Si in aluminum, eutectic α+Si, complex-doped aluminides of rare-earth metals of variable composition AlxSiyREMz and AlxSiyFezREMν). A correlation between the solubility of silicon in α-solid solution and its microhardness is found. To increase microhardness of the eutectic and hardness of the AK7ch alloy, it is necessary to add the synthesized ligature in the amount of 0.1 wt.%.

Highlights

The use of a composite aluminum base master alloy with rare-earth and other transition metals (Ce, La, Pr, Y, Sc, Sr, Zr, Ti, etc.) containing metal reinforcing base micro- and nanoscale compounds like rear earth metals (REM) aluminides has become a promising trend in improving the functional properties of aluminum alloys
The presence of the AlxSiyFezREMν aluminide with an admixture of manganese and α+Si eutectic is confirmed by the peaks of the content of these elements on the distribution curves of the elements (Fig. 2)
1) Structural components of the Al-Y-Ce-La master alloy are identified by the method of micro X-ray elements analysis: - metal base consists of crystals of pure aluminum and Al+AlxRzMy eutectics; microhardness of pure aluminum is 254 MPa; nanohardness - 1500 MPa; - yttrium-containing REM aluminide has Al3Y stoichiometry; microhardness value is 6547 MPa; nanohardness - 9627 MPa; - cerium-containing REM aluminide has the Al11REM3 = Al3.66REM stoichiometry (Al3.66Ce, Al3.66La); microhardness - 4695 MPa; nanohardness - 8560 MPa

Summary

Introduction

The use of a composite aluminum base master alloy with rare-earth and other transition metals (Ce, La, Pr, Y, Sc, Sr, Zr, Ti, etc.) containing metal reinforcing base micro- and nanoscale compounds like REM aluminides has become a promising trend in improving the functional properties of aluminum alloys. There are few publications on the problem of the effect of REM master alloy on modification of silumin [1,2,3,4]. There is no systematic study of the Al-Y-Ce-La master alloy effect on the structure formation, segregation processes and microhardness of structural components of the AK7ch alloy. % at the variation interval of 0.1 wt.%) on structure formation, elements distribution as well as microhardness of structural components and hardness of AK7ch (AL9) alloy The present work speaks on the effect of various additives of the synthesized Al-Y-CeLa master alloy (from 0 to 0.5 wt. % at the variation interval of 0.1 wt.%) on structure formation, elements distribution as well as microhardness of structural components and hardness of AK7ch (AL9) alloy.

Methods

Results

Conclusion