Microstructural refinement in an ultra-high strength martensitic steel via equal channel angular pressing

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:725

Article

Gibbons, S. L.¹  Abrahams, R. A.¹  Vaughan, M. W.²  Barber, R. E.²  Harris, R. C.¹  Arroyave, R.²  Karaman, I² 

[1] Air Force Res Labs, Munit Directorate, Eglin AFB, FL 32542 USA

[2] Texas A&M Univ, Dept Mat Sci Engn, College Stn, TX 77843 USA

关键词: CALPHAD;    Ultra-high strength steel;    Equal channel angular pressing;    Grain refinement;    Martensitic steel;   

DOI  :  10.1016/j.msea.2018.04.005

来源: Elsevier

【 摘 要 】

In this work, a CALPHAD thermodynamic model is used to assess the thermodynamic stability of austenite in an Ultra-High Strength Martensitic Steel (i.e., Eglin Steel) in order to refine parent austenite-grain sizes, via high temperature equal-channel angular pressing (ECAP). The parent austenite-grain sizes are reduced from 188 mu m to 14.8 mu m, which in turn, led to the refinement of martensite lath sizes. This approach produced a yield strength of 1.68 GPa, ultimate strength of 1.98 GPa, and an elongation of 16.1%. Overall, this method reduced development cycle times and achieved alloy performance on par with Ni-Co secondary hardening steels.

【 授权许可】

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