Effect of MnS inclusion morphology on elongation of Ti-microalloyed steel after cold rolling and continuous annealing processing

doi:10.13251/j.issn.0254-6051.2023.07.013

Abstract

Abstract: Taking Ti-microalloyed steel as the research object, the evolution behavior of MnS inclusions during the cold rolling process was analyzed by using OM, SEM, etc. Subsequently, the specimens with different deformation amounts were annealed, and their tensile properties and hardness were tested to analyze the influence of MnS inclusion morphology on fracture behavior. The results show that with the increase of cold rolling deformation, the maximum length of MnS inclusions increases, and at the same time, the morphology of MnS inclusions changes from banded to intermittent short linear or granular. With the increase of cold rolling reduction, the elongation of the specimen gradually deteriorates, mainly due to the increase in the interface area of the loading direction caused by granular MnS inclusions, which promotes the initiation of interface cracks.

Key words: MnS inclusion, Ti-microalloyed steel, cold rolling and annealing, elongation, fracture morphology

CLC Number:

TG146

Huang Weili, Li Hongbin, Wang Xingjuan, Chen Liansheng, Tian Yaqiang, Niu Yuewei, Chen Siping. Effect of MnS inclusion morphology on elongation of Ti-microalloyed steel after cold rolling and continuous annealing processing[J]. Heat Treatment of Metals, 2023, 48(7): 73-78.

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