Study of Direct Quenching and Tempering Process of a Low Carbon Equivalent 960 MPa Grade Steel

Abstract:

The chemical composition of a 960 Mpa grade high strength steel with low carbon equivalent was designed. Effect of direct quenching and tempering process on the microstructure and mechanical properties of the experimental steel was studied. Results showed that fine lath martensite was obtained after controlled rolling and direct quenching. With tempering temperature increasing, the mechanical properties showed different trends for different tempering stages. And this had a direct relationship with the microstructure evolution. The matrix recovery softening, carbon desolution and precipitation of nanomicroalloy carbides influenced the strength change. With increase of tempering time, the strength decreased and toughness improved. Experimental steel tempered at 450 °C for 40min could obtain the best mechanical properties, which meet the requirement with a large impact energy margin.

• Periodical: Advanced Materials Research (Volume 744)
• Pages: 329-333
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.744.329
• Online since: August 2013
• Authors: Feng Lu, Chao Wang, Yuan Yuan Li, Long Lu, Zhao Dong Wang, Guo Dong Wang
• Keywords: 960MPa Grade Steel, Direct Quenching, Low Carbon Equivalent, Microstructure, Property, Tempering

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