Investigation of the Pipe Weld for Brittle Metal Fracture

V.B Kulnevich,E.V Mal’Kova,S Bratan,S Roshchupkin

doi:10.1051/matecconf/202134601016

V.B Kulnevich, E.V Mal’Kova + Show 2 more

Open Access

https://doi.org/10.1051/matecconf/202134601016

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Abstract

The article presents the results of studies of artificial strain aging of pipe steels. The effect of deformation aging on the mechanical properties of steel during tensile tests has been determined.

Highlights

Aging processes occurring in welded joints during long-term operation have similar deformation mechanisms and deformation aging fracture morphology reproduced in laboratory conditions
There is aging of the metal, which manifests itself in a change in its properties after a certain period of time at normal or elevated temperatures, as well as strain aging in which the metal changes its properties after plastic deformation at temperatures below the recrystallization temperature [3]
The main factors contributing to the deformation aging of the metal are preliminary cold plastic deformation, heating temperature and time of structural and deformation processes associated with the distribution of cementite, redistribution of impurity atoms, accumulation of irreversible microdeformations, formation and decomposition of carbide and nitride particles, etc

Summary

Relevance of the research

Natural aging of a metal is a long-term process and the selection of an analogue of such aging that allows it to be simulated in a short time is important This is especially true for pipelines and other elements that transport oil and gas products and are in operation for a long time, since the aged metal cannot withstand the loads and collapse [1, 2]. There is aging of the metal, which manifests itself in a change in its properties after a certain period of time at normal or elevated temperatures, as well as strain aging in which the metal changes its properties (embrittles) after plastic deformation at temperatures below the recrystallization temperature [3] Both types of aging lead to a decrease in the ductility of steel and to a decrease in the bearing capacity, in particular of welded joints. Https://doi.org/10.10 51/matecconf /202134601016 temperature effects (cutting, welding, insulation) and, in addition, pipelines have been in operation for a long time

Research object

Theoretical justification of the research

Conclusion