Research on Torsion Beam with High Strength Steel Materials Forming

Abstract:

In order to study the temperature field, stress field, strain field, thinning rate and phase distribution in the hot forming process of torsion beam. The finite element software was used in this paper. Study found: Due to the different regions of part contact with the mould in the different order, the maximum principal strain area is in the highest temperature region, the maximum principal stress area is located in the lower temperature region; In the process of hot forming, the slow cooling rate of the part is 77°C/S, which is greater than critical cooling rate of martensitic transformation that is 30°C /S; With the increase of the initial temperature of sheet metal, the maximum content of austenite and thinning rate of the parts increase, and the forming quality of the parts decreases; With the increase of stamping speed, the thinning rate of parts is violent fluctuation. When the stamping speed is too large, the temperature of parts is greater than the martensite transformation temperature in some regions at the end of forming; With the increase of friction coefficient, the thinning rate and the minimum content of martensite increase at the beginning and then decrease, the maximum content of austenite decreases at the beginning and then increases. Research shows that: when the initial temperature of blank is 850°C, stamping speed is75mm/s and coefficient of friction is 0.45, the quality of the parts is the best and thinning rate is 5.804%. At the end of forming, the minimum temperature of parts is 285°C; minimum martensite content is 75.63% and the maximum austenite content is 24.36%.

• Periodical: Key Engineering Materials (Volume 723)
• Pages: 136-141
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.723.136
• Online since: December 2016
• Authors: Kai Yu, Fei Xiong, Kai Liu, He Fa Cheng*
• Keywords: Austenite, Cooling Rate, Hot Forming, Martensite, Thermal Mechanical Coupling

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