Effect of Overaging Temperature on the Mechanical Properties of Ultra-High Strength Multiphase Steel

Abstract:

Overaging after intercritical annealing of ultra-high strength multiphase steel was conducted in a continuous annealing simulator of the laboratory. The effect of overaging temperature on the mechanical properties of multiphase steel has been studied by observing the microstructural evolution during overaging. The results have shown that multiphase microstructures containing ferrite, martensite, bainite and retained austenite were obtained by overaging treatments after intercritical annealing in ultra-high strength steel, and overaging temperatures affected all constituents of the microstructure. UTS and YS dereased with increasing overaging temperature, and TEL decreased after overaging at 350°C. A good combination of ultimate tensile strength (1400MPa), yield strength (795MPa), and total elongation (15%) was exhibited for the specimen overaged at 250°C. This was attributed to synthetic action of all constituents of ultra-high strength steel microstructure.

• Periodical: Applied Mechanics and Materials (Volumes 556-562)
• Pages: 249-252
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.556-562.249
• Online since: May 2014
• Authors: Zhuang Li*, Zhen Zheng, Da Tong Qiu, Li Zhe Guo, Xin Gao, Tao Yu, Zhao Hua Li
• Keywords: Bainite, Intercritical Annealing, Multiphase Steel, Overaging Temperature, Ultra-High Strength

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