Study of the Microstructure and Mechanical Properties of a Medium Manganese Quenching and Partitioning (Q&P) Steel

Abstract:

The microstructure and mechanical properties of a medium manganese quenching and partitioning (Q&P) steel for automobile were investigated by optical microscope (OM), scanning electron microscope (SEM), X-ray diffraction (XRD) and mechanical property test. The grain size and recovery degree were greatly affected by annealing temperature normally. The result shows that the medium manganese steel after quenching and partitioning (Q&P) heat treatment exhibited good mechanical properties. The maximum tensile strength and yield strength was 1280MPa and 1421MPa at 600°C, respectively. Additionally, the product of strength and plasticity could reached to 40472MPa×% at 640°C. Annealing temperature also had a great influence on the volume of retained austenite which increases linearly with the rise of annealing temperature as well.

• Periodical: Materials Science Forum (Volume 850)
• Pages: 659-663
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.850.659
• Online since: March 2016
• Authors: Xiao Gang Li*, Ai Min Zhao, Hong Hong Zheng, Shao Heng Sun, Hong Xiang Yin
• Keywords: Mechanical Properties, Medium-Manganese Steel, Plasticity, Product of Strength, Q&P Heat Treatment, Retained Austenite

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