Authors: JaeIl Jung Naixie Zhou Jian Luo
Publish Date: 2012/09/05
Volume: 47, Issue: 24, Pages: 8308-8319
Abstract
The effects of seven sintering aids 05 at Ni Co Fe Cr Zr Nb and Pd on the densification of Mo–Si–B alloys of six different compositions Mo Mo–02Si Mo–02Si–002B Mo–25Si–25B Mo–7Si–5B and Mo–89Si–77B at are systematically investigated It was found that Ni Co and Fe are effective in enhancing densification of Mo–Si–B alloys and Ni is the most effective sintering aid This study supports a previously proposed hypothesis that activated sintering results from enhanced mass transport in the sinteringaidinduced quasiliquid intergranular films a type of grain boundary complexion The relative effectiveness of these sintering aids can be rationalized by analyzing several key thermodynamic parameters that control the stability of premeltinglike grain boundary complexions Future studies are needed to develop interfacial thermodynamic models and methods for computing “grain boundary complexion phase diagrams” for multicomponent systems which can be a useful component for the “Materials Genome” project that will enable better predictions of the activated sintering and other materials phenomenaWe would like to thank Zhao Zhang for experimental assistance in collecting partial data reported in Fig 3 We gratefully acknowledge the financial support from the US Air Force Office of Scientific Research AFOSR under the grant no FA95501010185 in the Aerospace Materials for Extreme Environments program and we thank our AFOSR program manager Dr Ali Sayir for his guidance and support We sincerely thank two anonymous reviewers for their constructive comments and suggestions
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