Microstructure-Impact Toughness Relationships in Quenched and Tempered Low Carbon Low Alloy Steels

Abstract:

The quantitative microstructure - impact toughness relationships in two batches of the same steel grade subjected to quenching and tempering (Q&T) have been established via characterization using EBSD technique and FIB visualization. The EBSD-based criterion for separation of structural constituents in microstructure of Q&T low carbon low alloy steels is proposed. Impact toughness differences between two steel batches subjected to nominally identical Q&T are caused by the changes in the volume fraction of structural constituents caused by various cooling conditions at quenching stage. High volume fraction of bainite containing more distorted bainitic ferrite and the highest amount of brittle cementite precipitates leads to the increase in strength and to the decrease in impact toughness.

• Periodical: Key Engineering Materials (Volume 887)
• Pages: 216-221
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.887.216
• Online since: May 2021
• Authors: M. Kantor, K. Vorkachev, K. Solntsev
• Keywords: EBSD, Impact Toughness, Low Carbon Low Alloy Steels, Microstructure, Quenching, Tempering

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