The Influence of Boron on Structural Properties of Martensitic 8-10%Cr-Steels

Abstract:

Four alloys on the basis of 8-10% CrWVTa steel were melted to study the influence of boron on the structure and precipitation behavior. Boron contents in the alloys amounted to 0.0083 and 0.1 wt.%, respectively. One batch was nearly free of boron. The individual alloys were examined metallographically and characterized in the initial state and after aging treatments up to 800 °C. It was found that the grains of boron-containing alloys were coarsened when the alloys were subjected to tempering. At the same time, the precipitate content was reduced. The different phases of precipitates were analyzed as primary carbides with tantalum and tungsten, and due to the higher content of boron BN, B(C, N), and (Fe, Cr)₂B. M₂₃C₆ was developed in all alloys after the heat treatment.

• Periodical: Materials Science Forum (Volumes 730-732)
• Pages: 877-882
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.730-732.877
• Online since: November 2012
• Authors: Edeltraud Materna-Morris, Michael Klimenkov, Anton Möslang
• Keywords: AES, Aging, Boron, Martensitic Steel, Precipitatation, SEM, TEM

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