Pressureless Sintering of Mo-Si-B Alloys with Fe Additive

  • Gaoyuan OuyangEmail author
  • Pratik K. Ray
  • Matthew J. Kramer
  • Mufit Akinc


The sintering behavior of Mo-Si-B alloys with iron as a sintering additive was investigated. The addition of small amounts of Fe effectively enhanced the densification of Mo-Si-B at temperatures below 1900 °C. The addition of 5 at.% Fe resulted in nearly full densification (97.0% of theoretical density) when sintered at 1750 °C for 2 h, while the unmodified Mo-Si-B alloy could be densified to only 66.8% of its theoretical density under these conditions. Addition of 0.5 at.% Fe and 2 at.% Fe increased the degree of densification of Mo-Si-B by 15.4 and 17.0%, respectively, and led to nearly full densification at 1900 and 1850 °C, respectively. Fe-Si-B eutectic liquid was formed at low temperatures and disappeared at high temperatures. We propose that the addition of Fe led to the formation of a transient liquid, facilitating liquid-phase sintering of the powder compacts.


EDS intermetallics liquid-phase sintering Mo-Si-B pressureless sintering SEM transition metal silicides ternary silicide borides XRD 



This work was supported by the AFOSR HTAM under contract #FA9550-11-1-201. The authors would like to thank Warren Straszheim for his help in the WDS analyses.


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Copyright information

© ASM International 2017

Authors and Affiliations

  • Gaoyuan Ouyang
    • 1
    Email author
  • Pratik K. Ray
    • 1
    • 2
  • Matthew J. Kramer
    • 1
    • 2
  • Mufit Akinc
    • 1
    • 2
  1. 1.Department of Material Science and EngineeringIowa State UniversityAmesUSA
  2. 2.Division of Materials Science and EngineeringAmes LaboratoryAmesUSA

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