Analysis on Fracture Morphology and Microstructure of T92 Steel after High Temperature Multiaxial Creep

Abstract:

The high temperature creep tests of standard specimen and double U-type notch specimen of T92 steel were carried out under different stresses at 650 °C. Then optical microscopy and scanning electron microscopy were used to observe the fracture morphology and microstructure. The results show that the multiaxial stress state leads to the creep fracture cracking initiation in notch. Under multiaxial stress state, the failure mode of T92 steel is transgranular and dimple plastic fracture, and is more obvious with the increase of creep life. Compared with under uniaxial stress state, the precipitates under multiaxial stress state are larger in size and quantity, and are much coarser.

• Periodical: Advanced Materials Research (Volumes 860-863)
• Pages: 967-971
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.860-863.967
• Online since: December 2013
• Authors: Xue Ping Mao, Xiao Wang*, Sai Dong Huang, Chao Li, Hong Xu, Yong Zhong Ni
• Keywords: Fracture Morphology, Microstructure, Multiaxial Creep, T92 Steel

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