Analysis on the Creep Mechanism of 12Cr-Mo-W-0.25V Steel Based on Long-Term Stress Relaxation Test Data

Abstract:

The current paper investigates on the creep behavior of 12Cr-Mo-W-0.25V heat resistant steel base on the long-term stress relaxation test data. It is shows that the stress relaxation curve can be divided into 2 stages: the high stress stage has higher apparent activation volume of 79~350 b³ and the low stress stage is 35~78 b³. Besides, the Helmholtz free energy at the high stress stage is 827~1034 kJ/mol which is higher than 210~252 kJ/mol of the low stress stage. Taking both apparent activation volume and activation energy into account, it is assumed that the high stress stage is mainly controlled by dislocation slip and the low stress stage is more related to diffusion.

• Periodical: Applied Mechanics and Materials (Volume 853)
• Pages: 158-162
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.853.158
• Online since: September 2016
• Authors: Jie Zhao*, Tie Shan Cao, Cong Qian Cheng, Hui Fang Li
• Keywords: Activation Energy, Activation Volume, Steady State Creep, Stress Relaxation

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