Study of Nano-Precipitate in High Strength Low Carbon Steel during Tempering by TEM

Abstract:

The behavior of nanoprecipitates of 800Mpa grade high strength low carbon steel during tempering has been studied. Transmission electron microscope (TEM), high resolution transmission electron microscopy (HRTEM) and energy dispersive spectrometry (EDS) were used to systematically analyze the morphology of precipitates and their grain orientation with matrix at different tempering temperatures. Experimental results confirm that the composition of these nanometer sized particles in the matrix was compound carbonitrides containing Ti, V, Mo and other elements. The precipitates of the as-received steel are (Nb,Ti)(C,N) at low tempering temperature, while those at high tempering temperature are composite carbides containing a variety of elements such as Mo, V, Ti and Nb. On the other hand, as tempering temperature increases, precipitates in the steel were slowly growing up and roughening according with the typical Oswald ripening mechanism; a sharp orientation relationship exists between precipitates and matrix.

• Periodical: Applied Mechanics and Materials (Volume 327)
• Pages: 123-127
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.327.123
• Online since: June 2013
• Authors: Long Fei Zuo, Li Li Qiu, Bin Hou, Xiao Hua Chen, Ming Wen Chen, Zi Dong Wang
• Keywords: HSLC, Nano-Precipitation, TEM

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