Effect of quenching temperature on microstructure and mechanical properties of medium manganese QP steel

doi:10.13251/j.issn.0254-6051.2020.05.033

Abstract

Abstract: Effect of different quenching temperature on microstructure and mechanical properties of medium manganese steel was studied by means of partial austenitization-quenching-partition process. The results show that with the increase of quenching temperature, the elongation of the tested steel increases first and then decreases, while the tensile strength decreases gradually. When the quenching temperature is 140 ℃, the total volume fraction of primary martensite and fresh martensite in the tested steel is the largest, so the tensile strength is the highest. The tested steel has the largest volume fraction of retained austenite and the highest elongation when the quenching temperature is 180 ℃, the comprehensive mechanical properties are the best and the product of tensile strength and plasticity is up to 30 328.2 MPa·% particularly. When the quenching temperature is increased to 200 ℃, the elongation and tensile strength of the tested steel decrease because of the decrease of retained austenite content and the hardness of fresh martensite.

Key words: Q&P process, quenching temperature, microstructure, mechanical properties

CLC Number:

TG161

Wang Yating, Wan Decheng, Feng Shuming, Li Jie. Effect of quenching temperature on microstructure and mechanical properties of medium manganese QP steel[J]. Heat Treatment of Metals, 2020, 45(5): 172-175.

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