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Effect of La Addition on Inclusions, Microstructures, and High-Temperature Mechanical Properties of As-Cast FeCrAl Alloys

  • Yang HeEmail author
  • Jianhua Liu
  • Yindong Yang
  • Alex McLean
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)

Abstract

The effects of La addition on the inclusions, microstructures, and high-temperature mechanical properties of as-cast FeCrAl alloys were investigated by using scanning electron microscope (SEM), energy disperse spectroscopy (EDS), and hot tensile tests. The characteristics of inclusions were examined, and further discussions focused on the analysis of thermodynamic calculations. The results showed that after La addition, AlN inclusions were likely to have cores of La-containing particles. Under the conditions of this study, La2O2S and La2O3 inclusions were the main La-containing precipitates and could act as the nucleus for the heterogeneous nucleation of δ-Fe to refine grains. The microstructure comparison of the two studied alloy ingots indicated that both the columnar and the equiaxed grains were refined after La addition. A series of tensile tests were carried out at temperatures from 973 to 1673 K under a constant strain rate of 1 × 10−3 s−1 to investigate the high-temperature mechanical properties. Both the tensile stress and the hot ductility were improved at the studied temperatures after La addition.

Keywords

FeCrAl alloys La addition Inclusions Microstructures Mechanical properties 

Notes

Acknowledgements

The authors gratefully acknowledge the financial support of this research by the National Science Foundation of China (Grant No 51374023).

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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  • Yang He
    • 1
    • 2
    Email author
  • Jianhua Liu
    • 1
  • Yindong Yang
    • 2
  • Alex McLean
    • 2
  1. 1.Institute of Engineering Technology, University of Science and Technology BeijingBeijingPeople’s Republic of China
  2. 2.Department of Materials Science and EngineeringUniversity of TorontoTorontoCanada

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