Effect of Heat Treatment on Microstructure and Mechanical Properties of TRIP Steel Sheets Containing Aluminium

Abstract:

Effect of heat treatment on microstructure of TRIP steel sheets containing aluminium was investigated on Gleeble 3500 thermal simulation testing machine. The microstructure evolution with variation of time and temperature was measured by means of optical metallography (OM) and X-ray stress analyzer. The tensile properties of TRIP steel at room temperature were also measured. It was shown that the maxium value of product of strength and ductility of 22858 MPa% was obtained by treatment of intercritical annealing temperature at 800 for 3 mins and bainitic holding temperature at 400 for 6 mins. The value of yield strength was mainly determinated by the volume fraction of bainite and the content of retained austenite was the key factor to result in optimum strength and ductility of TRIP steel. In addition, the properties of TRIP steel were markedly decreased because martensite, which was deleterious to the ductility, was present in microstructure of the steel soaking at bainitic temperature 350^。C for 6 mins.

• Periodical: Advanced Materials Research (Volumes 391-392)
• Pages: 554-558
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.391-392.554
• Online since: December 2011
• Authors: Yi Gao, Zhong Ping He, Yan Lin He, Lin Li, Ren Yuand Fu, Lei Zhou
• Keywords: Martensite, Product of Ductility, Product of Strength, TRIP Steel Sheets Containing Aluminium, Yield Strength

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