International Journal of Metalcasting

, Volume 9, Issue 4, pp 19–26 | Cite as

Solidification Microstructure of HK Heat Resistant Steel

  • Majid Abbasi
  • Mahdieh Vahdatnia
  • Ali Navaei


The as-casr microstructure of HK heat resistant steel produced by the investment casting process has been investigated. The pouring temperature and cooling method effects on the austenite grain size and shape, segregation of alloying elements and formation of eutectic carbides have been evaluated herein. Microscopic studies have shown tliat the microstructure of the steel consists of dendritic austenite with carbides in the grain boundaries and dendritic arm spaces. Decreasing the pouring temperature converts large columnar grains to small equiaxed grains and prevents the large eutectic carbides in the grain and dendritic boundaries. Also, increasing the cooling rate can decrease the formation of grain boundary carbides.

Key wards

HK steel heal resistant steel investment casting solidification microstructure eutectic carbide 


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Copyright information

© American Foundry Society 2015

Authors and Affiliations

  • Majid Abbasi
    • 1
  • Mahdieh Vahdatnia
    • 1
  • Ali Navaei
    • 1
  1. 1.Department of Materials EngineeringBabol Noshirvani University of TechnologyBabolIran

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