Influence of thermo-mechanical treatment in ferritic phase field on microstructure and mechanical properties of reduced activation ferritic-martensitic steel

7th National Conference on Processing and Characterization of Materials

Prakash, K.^1 ; Vanaja, J.^2 ; Laha, K.^3 ; Nageswara Rao, G.V.S.^1

Department of Metallurgical and Materials Engineering, National Institute of Technology, Warangal, India^1

Creep Studies Section, Indira Gandhi Centre for Atomic Research, Kalpakkam

603102, India^2

AUSC Mission Directorate, Noida UP

201305, India^3

关键词: Creep rupture strengths;    Creep strengths;    Dislocation densities;    Ferritic microstructure;    Martensitic structures;    Microstructure and mechanical properties;    Prior austenite grains;    Reduced activation ferritic-martensitic;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/338/1/012027/pdf
DOI  :  10.1088/1757-899X/338/1/012027

来源: IOP

【 摘 要 】

The present study focuses on the evaluation of microstructure and mechanical properties of reduced activation ferritic-martensitic (RAFM) steel (9Cr-1W-0.06Ta) subjected to thermo-mechanical treatment (TMT) in ferritic phase field. The results obtained were compared with the steel in conventional normalised plus tempered (N+T) condition. The microstructure of the steel in N+T and TMT conditions was assessed by optical and scanning electron microscopes. Hardness, tensile and creep studies were carried out and the results were correlated with the microstructural studies. While the TMT processed steel resulted in coarser prior austenite grains and exhibited ferritic microstructure with large distribution of fine M23C6and MX precipitates, the N+T steel reveals tempered martensitic structure with finer prior austenitic grains with coarser M23C6and MX precipitates. Although ferritic structure is present in TMT processed steel, it exhibits better tensile and creep rupture strengths than N+T steel due to the presence of increased dislocation density and finer distribution of precipitates.