Cause analysis of abnormal microstructure in EA1N axle steel after normalizing

doi:10.13251/j.issn.0254-6051.2025.03.049

Abstract

Abstract: The abnormal coarse pearlitic colonies observed in the microstructure of EA1N axle steel after conventional normalizing treatment was discussed and the causes of these abnormal coarse pearlitic colonies, as well as the effects of normalizing temperature and subsequent cooling rate on the microstructure of the EA1N axle steel were analyzed. The results show that the formation of coarse pearlitic colonies is related to carbon segregation in the EA1N axle steel, normalizing temperature, and subsequent cooling rate. The higher the normalizing temperature, the coarser the abnormal pearlitic colonies become. The slower the cooling rate after normalizing treatment, the easier it is to form pearlitic colonies, and the more severe the coarsening of the colonies.

Key words: EA1N axle steel, abnormal microstructure, normalizing, pearlite cluster

CLC Number:

TG111.5

Wu Zhonghua, Wang Songwei. Cause analysis of abnormal microstructure in EA1N axle steel after normalizing[J]. Heat Treatment of Metals, 2025, 50(3): 307-311.

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