Isothermal normalizing of TL-4521 steel for gear by residual heat after forging

doi:10.13251/j.issn.0254-6051.2020.12.017

Abstract

Abstract: Taken TL-4521 steel as the research object, the isothermal normalizing process utilizing residual heat after simulated forging was carried out on Gleeble-3800 thermal simulation testing machine, and the effects of cooling rate, isothermal holding time and deformation on microstructure and hardness were analyzed. The results show that with the increase of cooling rate after warm forging, the ferrite content decreases, the microstructure is refined significantly, and the hardness increases; the longer the holding time, the more sufficient pearlite is, and the microstructure tends to be homogenized, and the hardness decreases. The larger the warm forging deformation, the more deformation bands are formed in austenite. During the subsequent cooling, the number of ferrite nucleation increases, the grains are refined, the deformation strengthening is significant, and the hardness increases.

Key words: TL-4521 steel, cutting, isothermal normalizing, microstructure, hardness

CLC Number:

TG156.4

Wang Huizhen, Zhai Yuewen, Zhou Leyu. Isothermal normalizing of TL-4521 steel for gear by residual heat after forging[J]. Heat Treatment of Metals, 2020, 45(12): 92-96.

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