<abstract xmlns="http://www.w3.org/1999/xhtml"> The paper deals with the identification of precipitates in the Cr-Mn-N steels after thermal exposure. The purpose of the study is to clarify the M2N precipitation by isothermal annealing at the temperatures of 750 and 900 °C with a holding time of 5, 10, 30 min, 1 hr. and 10 hrs. Microstructure of austenitic steel was characterised by the typical presence of annealing twins. Stepwise etching was observed at the holding time of 5 and 10 minutes, but at the holding time of 30 minutes, secondary particles were precipitated at the grain boundaries. Corrosion tests revealed that holding time significantly affected steel structure. M2N is the dominant precipitate, but the occurrence of σ-phase was occasionally observed especially at the interface of discontinuous precipitation and austenitic matrix. Slight increase of hardness at the grain boundaries was caused due to the precipitation of secondary phases during isothermal holding. The maximum hardness of 294 HV was measured on the sample isothermally annealed at 750 °C and holding for 10 hrs. The research provides theoretical basis for the heat affecting of steels, such as, for example, in welding.</abstract>

The paper deals with the identification of precipitates in the Cr-Mn-N steels after thermal exposure. The purpose of the study is to clarify the M2N precipitation by isothermal annealing at the temperatures of 750 and 900 °C with a holding time of 5, 10, 30 min, 1 hr. and 10 hrs. Microstructure of austenitic steel was characterised by the typical presence of annealing twins. Stepwise etching was observed at the holding time of 5 and 10 minutes, but at the holding time of 30 minutes, secondary particles were precipitated at the grain boundaries. Corrosion tests revealed that holding time significantly affected steel structure. M2N is the dominant precipitate, but the occurrence of σ-phase was occasionally observed especially at the interface of discontinuous precipitation and austenitic matrix. Slight increase of hardness at the grain boundaries was caused due to the precipitation of secondary phases during isothermal holding. The maximum hardness of 294 HV was measured on the sample isothermally annealed at 750 °C and holding for 10 hrs. The research provides theoretical basis for the heat affecting of steels, such as, for example, in welding.

Identification of Precipitates in Cr-Mn-N Based Steel After Thermal Exposures

Slovak University of Technology in Bratislava, Faculty of Materials Science & Technology in Trnava, Department of Welding and Foundry, J. Bottu 25, 917 24 Trnava, Slovak Republic

Research Papers Faculty of Materials Science and Technology Slovak University of Technology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

{"article-title":"Identification of Precipitates in Cr-Mn-N Based Steel After Thermal Exposures"}

The paper deals with the identification of precipitates in the Cr-Mn-N steels after thermal exposure. The purpose of the study is to clarify the M2N...

Identification of Precipitates in Cr-Mn-N Based Steel After Thermal Exposures

Published Online: Nov 25, 2014

Page range: 51 - 57

DOI: https://doi.org/10.2478/rput-2014-0027

Keywords
stainless steel, precipitation, corrosion, corrosion resistance

© by Michal Ondruška

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Identification of Precipitates in Cr-Mn-N Based Steel After Thermal Exposures

Published Online: Nov 25, 2014

Page range: 51 - 57

DOI: https://doi.org/10.2478/rput-2014-0027

Keywordsstainless steel, precipitation, corrosion, corrosion resistance

© by Michal Ondruška

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
stainless steel, precipitation, corrosion, corrosion resistance