Elevated Temperature Behavior of Creep and Fatigue in Welded P92 Steel

2003 ◽  
Vol 17 (08n09) ◽  
pp. 1621-1626 ◽  
Author(s):  
Byeongsoo Lim ◽  
Bumjoon Kim ◽  
Moonhee Park ◽  
Sungjoon Won
Keyword(s):  
High Temperature ◽  
Weld Metal ◽  
Base Metal ◽  
Power Plants ◽  
Test Method ◽  
P92 Steel ◽  
Creep Properties ◽  
High Temperature Materials ◽  
Materials Used ◽  
Small Punch Creep Test

Fatigue strength and life of weldment at high temperature is very important for high temperature materials used in power plants. In this study, creep properties of weld metal, HAZ and base metal of P92 steel were evaluated by SP (small punch) creep test method. Fatigue crack growth behaviors in weld metal, HAZ and base metal of P92 steel were investigated at high temperature. Microstructure and microhardness of the weldment were also investigated for better analysis.

scholarly journals Influence of long-term high-temperature action on impact toughness of base metal and weld metal of 22K steel welded joint

2021 ◽  
Vol 64 (7) ◽  
pp. 498-509
Author(s):  
S. A. Nikulin ◽  
S. O. Rogachev ◽  
V. A. Belov ◽  
A. A. Komissarov ◽  
V. Yu. Turilina ◽  
...  
Keyword(s):  
High Temperature ◽  
Weld Metal ◽  
Base Metal ◽  
Nuclear Power ◽  
Power Plants ◽  
Welded Joint ◽  
Low Carbon ◽  
Brittle Transition ◽  
Vessel Material

One of the applications of construction low-carbon 22K steel (AISI 1022 type) is as a material for the vessel of a core catcher (CC) for nuclear power plants with VVER reactors. In the event of severe beyond design basis accident, the CC-vessel will be under conditions of prolonged hightemperature impacts, which can significantly change the structural state and lead to degradation of mechanical properties of the vessel material. Data on the effect of such actions on the mechanical properties and fracture resistance of welds (the properties of which usually differ from those of the base metal) from low-carbon steels are very limited in the literature. This makes it difficult to guarantee the reliability and safety prediction of CC. The purpose of this work was to carry out the comparative Charpy V-notch impact tests of the samples of base metal and weld metal of the 22K steel welded joint before and after long-term high-temperature heat treatment, simulating the thermal effect on the reactor vessel material of nuclear power plants during severe accidents. Welded joints of 22K steel sheets were obtained by the method of automatic argon-arc welding with a consumable electrode (welding wire SV-08G2S was used) in accordance with PNAE G-7-009–89. Based on the test results, the ductile–brittle transition curves were plotted and analysis of fracture surfaces after tests was carried out. The influence of structural factors on the impact toughness has been studied. It is shown that prolonged high-temperature exposure leads to an increase in the temperatures of beginning and end of the ductile-brittle transition by 30 – 50 °C and to the expansion of range of the ductile-brittle transition temperature by 15 – 25 °C of both base metal and weld metal of the welded joint.

scholarly journals High temperature materials: properties, demands and applications

2020 ◽  
Vol 74 (4) ◽  
pp. 273-284
Author(s):  
Marko Simic ◽  
Ana Alil ◽  
Sanja Martinovic ◽  
Milica Vlahovic ◽  
Aleksandar Savic ◽  
...  
Keyword(s):  
High Temperature ◽  
Gas Turbines ◽  
Nuclear Power ◽  
Power Plants ◽  
Turbine Engines ◽  
High Temperature Materials ◽  
Wide Range ◽  
Different Types ◽  
Industrial Gas Turbines ◽  
Materials Used

High-temperature materials are used in a wide range of industries and applications such as gas turbine engines for aircrafts, power and nuclear power plants, different types of furnaces, including blast furnaces, some fuel cells, industrial gas turbines, different types of reactors, engines, electronic and lighting devices, and many others. Demands for high-temperature materials are becoming more and more challenging every year. To perform efficiently, effectively and at the same time to be economically viable, the materials used at high temperatures must have certain characteristics that are particularly expected for applying under such extreme conditions, for example, the strength and thermal resistance. In the present review, some important requirements that should be satisfied by high temperature materials will be discussed. Furthermore, the focus is put on refractory concretes, ceramics, intermetallic alloys, and composites as four different categories of these materials, which are also considered in respect to possibilities to overcome some of the current challenges.

NIMROD 617KS

Alloy Digest ◽  
2002 ◽  
Vol 51 (5) ◽  
Keyword(s):  
Fracture Toughness ◽  
High Temperature ◽  
Weld Metal ◽  
Tensile Properties ◽  
Base Metal ◽  
Heat Treating ◽  
Nominal Composition

Abstract Nimrod 617KS is an Inconel-type consumable with a nominal composition of nickel, 24% Cr,12% Co, and 9% Mo and is used to join UNS N06617 and Nicrofer 6023 to themselves. The alloy is designed for high-temperature service and is often used as the weld metal in dissimilar cases to ensure the weld is as strong as the base metal. This datasheet provides information on composition, hardness, and tensile properties as well as fracture toughness. It also includes information on heat treating and joining. Filing Code: Ni-583. Producer or source: Metrode Products Ltd.

Apply the Acoustoelastic Method to Determine Residual Stresses in Welded Joints

NDT World ◽  
2020 ◽  
pp. 10-17
Author(s):  
Arkady Kamyshev ◽  
Aleksandr Danilov ◽  
Lev Pasmanik ◽  
Aleksandr Getman ◽  
Dmitry Kuzmin ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Weld Metal ◽  
Base Metal ◽  
Welded Joints ◽  
Nuclear Power ◽  
Power Plants ◽  
Stress Measurement ◽  
Metal Structure ◽  
Mechanical Tests ◽  
Residual Welding

The problem of maximum stresses estimation in the weld metal, where the direct measurements are not possible due to the influence of the metal structure on the measurement error, was solved. The influence of features of welding joints manufacturing technology on the structure of the weld metal was also determined. We use several reference welded joints of pipelines at nuclear power plants in our studies. Instrumental estimation of acoustoelasticity parameters in the weld metal in welded joints and in adjacent areas of the base metal was used together with computational modeling of the residual welding stresses distributions. Results obtained demonstrate that the error of stress measurement in the metal in the joint, which is related to the structure of the weld metal, is comparable to the material yield strength. Due to that a direct measurement of the maximum values of welding stresses is not possible. Comparison of results of acoustoelasticity parameters measurements with results of the metal macrostructure studies and mechanical tests allowed us to determine the relationship between peculiarities of structure of the weld metal sections at vertical joints with their tendency to brittle destruction. We propose and justify the NDT method of residual welding stresses in the weld metal. It is based on the principle of residual stresses balancing and employs the results of stress measurements in the base metal by acoustoelasticity. Applicability of non-destructive testing of acoustoelasticity parameters to identify the areas of welded joints with a higher tendency to brittle fracture is also justified.

Appraisement of Creep Properties of 12Cr1MoV Steel by Small Punch Creep Test Method

2005 ◽  
Vol 492-493 ◽  
pp. 545-550
Author(s):  
Gang Chen ◽  
Peng Cheng Zhai ◽  
Ai-Jun Shao
Keyword(s):  
High Temperature ◽  
Creep Strain ◽  
Material Properties ◽  
Test Method ◽  
High Temperature Creep ◽  
Creep Properties ◽  
Central Deflection ◽  
Small Punch ◽  
Temperature Creep ◽  
The Relationship

The numerical simulation for the Small Punch creep (SP-C) tests is conducted using a Finite Element method. The objective of the present study is to obtain the deformation states of the SP-C specimen and to estimate the feasibility of SP-C test method for high-temperature creep properties. The emphasis is put on the relationship between the equivalent creep strain and the central deflection of the SP-C specimen. The time history of central deflection and equivalent creep strain is obtained by finite element method and the effects of the load, temperature and material properties on the relationship of central deflection and equivalent creep strain are discussed. From the numerical results, the relationship between the central deflection and the equivalent creep strain is approximately independent of load, temperature, and material properties. As a farther result, the high temperature creep properties of the 12Cr1MoV steel are appraised by numerical simulation. The results are in good agreement with the results from the standard test method. The results indicate that the small punch test technique is an effective method for the evaluation of the high-temperature creep properties of materials.

Creep Properties of Nitrogen-Alloyed Type 316L Stainless Steel

2007 ◽  
Author(s):  
M. D. Mathew ◽  
C. Girish Shastry ◽  
S. Latha ◽  
K. Bhanu Sankara Rao
Keyword(s):  
Stainless Steel ◽  
Weld Metal ◽  
Base Metal ◽  
Weld Joint ◽  
316L Stainless Steel ◽  
Rupture Strength ◽  
Creep Rupture Strength ◽  
Creep Properties ◽  
Type 316L ◽  
Type 316L Stainless Steel

Type 316L stainless steel (SS) alloyed with 0.06–0.08 wt% nitrogen is the principal structural material for the sodium circuit components of India’s Prototype Fast Breeder Reactor. Carbon in the range of 0.045–0.055 wt% and nitrogen in the range of 0.06–0.10 wt% have been specified for the welding consumable to provide weld joints with creep strength as close as possible to that of the base metal. Design of the components is based on RCC-MR fast reactor code. Creep properties of the plates and the welding consumables, which were produced by the Indian industry, have been studied at 873 and 923 K. Creep rupture strength of the weld joint was found to be comparable with that of the base metal, implying a weld strength reduction factor close to unity. Creep rupture strength of the weld metal was found to be lower than that of the weld joint at 923 K whereas it was comparable to that of the weld joint at 873 K. The creep failure location shifted from the base metal to the weld metal with increase in test temperature from 873 K to 923 K. The base metal and the weld joint satisfied the average strength requirements specified by RCC-MR code. Addition of nitrogen was found to increase rupture strength by about 35% as compared to that of 316 SS. Rupture elongation decreased in the order base metal > weld joint > weld metal. Phenomenological observations on creep behaviour have been rationalized based on the mechanistic aspects of deformation and damage and microstructural changes.

Application of Nonlinear Elastic Wave Spectroscopy in the Field of Nuclear Energy

2020 ◽  
Vol 7 (2) ◽  
Author(s):  
J. Patera ◽  
J. Jansa
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Elastic Wave ◽  
Power Plants ◽  
Nuclear Energy ◽  
Test System ◽  
Test Method ◽  
Nonlinear Elastic ◽  
Nonlinear Elastic Wave ◽  
High Temperature High Pressure

Abstract In the field of nuclear energy, two particular applications are considered—the measurement of biological shielding concrete and measurement of high-temperature high-pressure piping. For the measurement of biological shielding concrete, a special manipulator was developed, which is applied through the ionization channels of VVER-440 power plants. Biological shielding concrete is covered on all sides with an 11 mm thick steel liner preventing its assessment using any conventional test method. For the measurement of high-temperature high-pressure piping, acoustic emission sensors installed in the LEMOP system (NPP Temelin) are used for both excitation and data acquisition. In operation, this piping is covered with glass wool insulation, but installed sensors on the waveguides make it possible to assess pipelines without removing the insulation. To demonstrate the material degradation, a set of concrete test specimens and a set of steel test specimens were made. Nonlinear elastic wave spectroscopy is a test method based on measuring the elastic–plastic response of the material whose plastic component is caused by microcracks. Part of this response may be caused by inhomogeneity of the material itself or the nonlinearity of the test system used, which is to be minimized in the measurement. Due to degradation, the number of microcracks increases, increasing the total nonlinear response of the material. The aim of this approach is to monitor the degradation of concrete and metallic materials based on the response of the test system to ultrasonic excitation.

Phase equilibrium and mechanical properties of Cr-Mo-Nb-Si-B alloys Composed of BCC and T2-silicide phase

MRS Advances ◽  
2019 ◽  
Vol 4 (25-26) ◽  
pp. 1491-1496 ◽  
Author(s):  
Daisuke Goto ◽  
Ken-ichi Ikeda ◽  
Seiji Miura
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Phase Equilibria ◽  
Power Plants ◽  
Thermal Power ◽  
Silicide Phase ◽  
Two Phase ◽  
New Class ◽  
High Temperature Materials ◽  
Si Content

ABSTRACTA new class of high-temperature materials based on refractory elements was investigated with an aim to improve the energy efficiency of thermal power plants. Alloys based on Nb and Mo composed of BCC solid solution (BCCss) (Nb-Mo) and T2-silicide (Nb,Mo)5(Si,B)3 are promising candidates as high-temperature materials. Further investigation on the alloy phase equilibria of this system is required to improve the mechanical properties and oxidation resistance through optimization of the phase compositions. Cr is one candidate to modify the properties of the alloy because Cr is expected to stabilize the T2 compound phase along with B. Here, the phase equilibria among BCCss and the T2 compound are widely investigated in the Cr-Mo-Nb-Si-B system, and a BCCss-T2 two-phase microstructure is found in Mo-rich alloys. The B/Si ratio in the T2 phase increases with the Cr content, while almost no B solubility was found in BCCss. As the Si content increases in alloys, the A15 silicide phase ((Cr, Mo, Nb)3Si) and/or Laves phase appear.Nanoindentation tests were conducted to investigate the mechanical properties of the BCCss phase of the alloys in the Cr-Mo-Nb-Si-B system. The nanohardness and reduced elastic modulus of these alloys tended to be higher with an increase in Cr.

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