Influence of Ti-rare earth addition on microstructure and toughness of coarse grain heat-affected zone in C-Mn steel

ZHANG Sheng-hua; SONG Bo; SONG Ming-ming; GAO Qi-rui

doi:10.13374/j.issn2095-9389.2017.06.005

Volume 39 Issue 6

Jun. 2017

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ZHANG Sheng-hua, SONG Bo, SONG Ming-ming, GAO Qi-rui. Influence of Ti-rare earth addition on microstructure and toughness of coarse grain heat-affected zone in C-Mn steel[J]. Chinese Journal of Engineering, 2017, 39(6): 846-853. doi: 10.13374/j.issn2095-9389.2017.06.005

Citation:

ZHANG Sheng-hua, SONG Bo, SONG Ming-ming, GAO Qi-rui. Influence of Ti-rare earth addition on microstructure and toughness of coarse grain heat-affected zone in C-Mn steel[J]. Chinese Journal of Engineering, 2017, 39(6): 846-853. doi: 10.13374/j.issn2095-9389.2017.06.005

Citation:

ZHANG Sheng-hua, SONG Bo, SONG Ming-ming, GAO Qi-rui. Influence of Ti-rare earth addition on microstructure and toughness of coarse grain heat-affected zone in C-Mn steel[J]. Chinese Journal of Engineering, 2017, 39(6): 846-853. doi: 10.13374/j.issn2095-9389.2017.06.005

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Influence of Ti-rare earth addition on microstructure and toughness of coarse grain heat-affected zone in C-Mn steel

doi: 10.13374/j.issn2095-9389.2017.06.005

1) School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
2) State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China
3) State Key Laboratory for Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China

Received Date: 2016-10-10

Abstract

Abstract

The influences of rare earth (RE) and Ti-RE complex treatment on the microstructures and toughness in the coarse grain heat-affected zone (CGHAZ) of C-Mn steel were investigated using a Gleeble-1500D thermal simulator with input heat energy of 65 kJ·cm^-1. The inclusions and impact fracture morphology were observed and analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX), and the microstructure was characterized using an optical microscope (OM). The results show that the microstructures in the CGHAZs of RE-and Ti-RE-treated samples are mainly grain boundary ferrite (GBF) + polygonal ferrite (PF) + intragranular acicular ferrite (IAF) and grain boundary ferrite + intragranular acicular ferrite, respectively. Inclusions in the RE-treated specimen are La₂O₂S + Mn-Al-Si-O + MnS, while those in the Ti-RE-treated specimen are La₂O₂S + TiO_x + Mn-Al-Si-O + MnS. The complex inclusions in Ti-RE-treated steel are smaller than those in RE-treated steel, and the size of IAF in Ti-RE-treated steel is smaller. The impact properties of the CGHAZ in Ti-RE-treated C-Mn steel is improved significantly, and the material is tougher than RE-treated steel.
- carbon-manganese steel,
- coarse grain heat-affected zone (CGHAZ),
- acicular ferrite (AF),
- microstructure,
- impact toughness

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References(14)

References

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