The Method of Eliminating Banded Structure and the Effects of Banded Structure on the Transverse Properties in 20G Steel

Abstract:

The transverse properties were inferior to the longitudinal properties for the existence of banded structure in 20G steel. In order to eliminate the banded structure and improve the transverse performance of 20G steel, different heat treatment processes were adopted. The results showed that conventional normalizing could reduce the banded structure and refine the grain sizes. When 20G was heated with 10°C/min heating rated and then held at 920°C for 2h, the banded structure in the steel was almost eliminated and the microstructure was homogeneous with fine grain size, the strength increased by 14%. The non-metallic inclusion and carbide in the microstructure leaded to stress concentration and separation with the base metal. To some extent, heat treatment can improve the distribution and form of non-metallic inclusions.

• Periodical: Applied Mechanics and Materials (Volumes 347-350)
• Pages: 1171-1175
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.347-350.1171
• Online since: August 2013
• Authors: Bin Wang, Hong Mei Hu, Cui Zhou
• Keywords: 20g Steel, Banded Structure, Grain Refinement, Heat Treatment

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