Characterization of microstructure of P92 heat-resistant steel elbow during high-temperature creep rupture process

doi:10.13251/j.issn.0254-6051.2025.01.036

Abstract

Abstract: Microstructure transformation of the clamping section (aging), deformation section (creep), and necking position (rupture) of P92 steel elbows during creep rupture at 630 ℃ and different stresses (175, 140, 130, and 100 MPa) was studied by using scanning electron microscopy, transmission electron microscopy, EBSD, etc. The results indicate that strain-induced precipitation coarsening occurs in the P92 steel elbows under creep conditions. After long-term aging, the morphology of the P92 steel changes from martensite lath to edge dislocation. The cracks near the rupture of the P92 steel initially expand into elliptical holes. After the Laves phase precipitates, the grain boundary strength decreases compared to the early stage, and the cracks transform into wedge and flower shapes.

Key words: P92 heat-resistant steel, elbow, high-temperature creep rupture, microstructure evolution

CLC Number:

TG162.8

Peng Xingna, Cong Xiangzhou, Peng Xiankuan, Tu Dejun, Qiao Yaxia. Characterization of microstructure of P92 heat-resistant steel elbow during high-temperature creep rupture process[J]. Heat Treatment of Metals, 2025, 50(1): 230-235.

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