PSI - Issue 23

Petr Haušild et al. / Procedia Structural Integrity 23 (2019) 179–184 Haušild et al. / Structural Integrity Procedia 00 (2019) 000 – 000

184

6

4. Conclusions

The microstructure, phase composition and mechanical properties after various durations of mechanical alloying were characterized in FeAl20Si20 (wt.%) prepared from different type of feedstock powders. The effect of using the pre-alloyed powders on kinetics of mechanical alloying in comparison with using the elemental powders can be summarized as follows: • The powder prepared from relatively soft pre-alloyed AlSi30 feedstock showed in the beginning of milling faster kinetics of mechanical alloying, probably by the effect of Si fine dispersion in the Al-Si eutectic. Yet, the complete solid solution formation did not occur faster than in the case of the powder prepared from the elemental feedstock powders. • The reason for equalized duration of the mechanical alloying process is probably the need for crushing coarser and relatively hard silicon particles added to balance the silicon content in AlSi30 pre-alloyed powder. However, increasing the content of Si in pre-alloyed Al-Si powder will probably not lead to further improvement (acceleration) of the process as the excess in Si would only result in higher content of (coarse) primary Si-phase in pre-alloyed Al Si powder. • The initially hard feedstock powders such as FeAl and FeSi delayed the kinetics of mechanical alloying. • Regardless the initial feedstock material, the final phase composition corresponding to predominantly Fe 3 Si with some content of FeSi was obtained in all combination of (pre-alloyed) feedstock powders.

Acknowledgements

This research was carried out in the frame of the projects 17-07559S (Czech Science Foundation) and CZ.02.1.01/0.0/0.0/16_019/0000778 (Centre of Advanced Applied Sciences).

References

Čech, J. , Haušild, P. , Kadlecová, V., Karlík, Čapek, J., M., Průša, F. , Novák P., 2019. Mechanical properties of FeAlSi powders prepared by mechanical alloying from different initial feedstock materials, Matériaux &Techniques 107, 207 . Haušild, P. , Karlík, M. , Čech, J. , Průša, F. , Nová, K. , Novák, P. , Minárik, P. , Kopeček, J. , 2018a. Preparation of Fe – Al – Si Intermetallic Compound by Mechanical Alloying and Spark Plasma Sintering. Acta Physica Polonica A 134, 724-728. Haušild, P. , Čech, J. , Karlík, M. , Průša, F. , Novák, P. , Kopeček, J. , 2018b. Nanoindentation Characterization of Mechanically Alloyed Fe-Al-Si Powders, Key Engineering Materials 784, 15-20. ISO 14577-2, 2015. Instrumented Indentation Test for Hardness and Materials Parameters. Novák, P. , Průša, F. , Nová, K. , Bernatiková, A. , Salvetr, P., Kopeček, J. , Haušild, P. , 2018. Application of Mechanical Alloying in Synthesis of Intermetallics. Acta Physica Polonica A 134 (2018) 720-723. Novák, P. , Michalcová, A., Voděrová, M. , Šíma, M., Šerák, J. , Vojtěch, D. , Wienerová, K., 2010. Effect of reactive sintering conditions on microstructure of Fe – Al – Si alloys. J. Alloys and Compounds 493, 81-86. Oliver, W.C., Pharr, G.M., 1992. Improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564-80. Stoloff, N.S., 1998. Iron Aluminides: Present Status and Future Prospects. Mater. Sci. Eng. A 258, 1-14.