The Influence Of Load History On Durability Of P92 Steel Used For The Construction Of Energy Pipelines

Abstract

The research material used in the study was the martensitic creep-resistant steel P92 used for the manufacture of pipes being part of power generation units subject to heavy load. The research problem focused on two issues. The first one was to analyze how the plastic deformation cumulated in the material in low-cycle fatigue conditions affects the characteristics of the material in creep conditions in a temperature of 600ºC. The other one was concerned with analysis of a reverse situation, i.e. how the initial plastic deformation of the material in creep conditions changes the mechanical characteristics of the steel under low-cycle fatigue conditions in a temperature of 600ºC.

Hydrogen pre-charging effects on the notch tensile properties and fracture behaviour of heat-affected zones of thermally aged welds between T24 and T92 creep-resistant steels

“…• C. The microstructure of P/T92 base material is typically formed of tempered lath martensite with finely dispersed intragranular MX (M = V, Nb; X = C, N) carbonitrides and intergranular M 23 C 6 (M = Cr, Fe) carbides at grain, block, and lath boundaries [17][18][19][20][21]. The most significant microstructural change in Grade 92 steels during their long-term ageing and/or creep exposure is the additional precipitation of intermetallic Fe 2 (W, Mo) based Laves phase, typically in the vicinity of M 23 C 6 carbides [19][20][21][22][23][24].…”

“…The most significant microstructural change in Grade 92 steels during their long-term ageing and/or creep exposure is the additional precipitation of intermetallic Fe 2 (W, Mo) based Laves phase, typically in the vicinity of M 23 C 6 carbides [19][20][21][22][23][24].…”

Ageing Effects on Microstructure, Mechanical Properties, and Fracture Behaviour of 9Cr-1.5Mo-1Co-VNbBN Martensitic Steel Welded Joint for High Temperature Application

“…The welded joints of high chromium tempered martensitic creep-resistant steel are frequently employed in construction of modern fossil-fired thermal power plants operating at supercritical and ultrasupercritical conditions [1]. Their main application area covers structural parts of thick section boiler components including high temperature header section and main steam pipelines [2][3][4]. It generally holds that local microstructure formation of individual weld regions, namely, the weld metal (WM), fusion zone (FZ), and heataffected zone (HAZ) depends on their location within the weldment and reached peak temperature during the weld preparation.…”