Wyniki wyszukiwania - BazTech

1

Long-term Annealing of NiCrAlY LENS Coating on 316L Steel

Szymański Krzysztof K.

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 4

116--120

EN

This article presents the results of a research on the behavior of NiCrAlY coating obtained by the LENS method on austenitic stainless steel type 316L under long-term annealing conditions at 1000°C for 25, 100 and 250 hours. The morphology of the NiCrAlY layer as a function of annealing time and temperature was characterized. The chemical composition and distribution of alloying elements were evaluated using scanning microscopy and micro-area chemical composition analysis. It was revealed that NiCrAlY coatings deposited by LENS method are characterized by good metallurgical quality. The long-term annealing of the NiCrAlY coating led to microstructural changes in the form of the disappearance of the original dendritic structure and the formation of a solid solution of nickel with chromium and a small amount of aluminum, as well as chromium α-Cr precipitates and Ni-Y-type phases. The effect of increasing iron concentration in the coating due to diffusion-to-core processes was also found.

2

Changes In Properties and Microstructure of High-Chromium 9-12%Cr Steels Due to Long-Term Exposure at Elevated Temperature

Zieliński A., Dobrzański J., Purzyńska H., Golański G.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 2B

957--964

EN

This paper presents the characteristics of the performance of P91 (X10CrMoVNb9-1), P92 (X10CrWMoVNb9-2) and VM12 (X12CrCoWVNb12-2-2) steels used for condition assessment of the pressure components of boilers with supercritical steam parameters. Studies on the mechanical properties, microstructure tests using scanning and transmission electron microscopy, and X-ray analysis of the phase composition of precipitates were performed for selected steels in the as-received condition and after long-term annealing. These steel characteristics are used for the evaluation of the microstructural changes and mechanical properties of the material of components after long-term service. The result of this study is the database of material characteristics representing the mechanical properties related to the microstructure analysis and it can be used for diagnosis of the components of pressure parts of power boilers.

3

Computer-assisted analysis of changes in the microstructure of P92 steel after exposure at elevated temperature

Zieliński A., Dobrzański J., Golański G., Sroka M.

Archives of Materials Science and Engineering

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2014

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Vol. 65, nr 2

77--86

EN

Purpose: The purpose of the work was to analyse the components of X10CrWMoVNb9-2 (P92) steel in initial state and after long-term annealing for up to 100,000 h at 600 and 650°C. Design/methodology/approach: The material for investigation was X10CrWMoVNb9-2 (P92) steel in the form of a Ø160x40mm tube. The images of microstructure were recorded using the scanning electron microscopy. The quantitative analysis of precipitates was carried out using the image analysis system NIKON EPIPHOT200 & LUCIA G v.5.03. Findings: The investigations of microstructure and the quantitative analysis of precipitates in the tested steel in initial state and after long-term annealing allowed the impact of temperature and time on stability of the microstructure of the tested steel to be evaluated. Practical implications: The presented method can be used for evaluation and qualification of structural changes in power station boiler components operating under creep conditions. Originality/value: The presented results of changes in the structure and in the precipitation processes are applied to evaluation of the condition of the elements in further industrial service.

4

Computer assisted evaluation of degree of exhaustion of T/P23 (2.25Cr-0.3Mo-1.6W-V-Nb) steel after long-term annealing

Sroka M., Zieliński A.

Archives of Materials Science and Engineering

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2013

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Vol. 64, nr 2

205--212

EN

Purpose: The method of image analysis and artificial intelligence methods in the evaluation of materials while working in creep conditions were proposed. The application of scanning electron microscopy in the correct assessment of the degree of exhaustion was of a demonstration character. Design/methodology/approach: For the material after long-term operation in the creep tests microstructure examination was performed in a scanning electron microscope. To assess the degree of exhaustion of the material, the computer program was used. Findings: The article demonstrates how to assess the state of the material using a computer program as an example of the application of computer methods for materials science. The verification was found to develop methodologies for assessing the correct level of exhaustion while working in steel material creep conditions. Practical implications: The presented method can be used for evaluation and qualification of structural changes in power station boiler components operating in creep conditions. Originality/value: The obtained results of changes in the mechanical properties, microstructure and in the precipitation processes are applied to the evaluating the condition of the elements in further industrial service.

5

Ddoświadczenia z zastosowania nowych stali do wytwarzania elementów kotłów na parametry nadkrytyczne

Dobrzański J., Zieliński A., Pasternak J., Hernas A.

Prace Instytutu Metalurgii Żelaza

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2010

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T. 62, nr 1

51-60

PL

W referacie przedstawiono charakterystyki nowych stali żarowytrzymałych stosowanych w budowie kotłów nadkrytycznych, w tym szczególnie wyniki badań cienko- i grubościennych złączy spawanych. Przedmiotem badań były niskostopowe stale bainityczne TP23 i TP24 oraz wysokostopowe martenzytyczne TP91, TP92, VM12 oraz austenityczna HR3C. Dokonano analizy doboru materiałów na przegrzewacze pary kotła nadkrytycznego. Przedstawiono charakterystyki struktury i właściwości mechanicznych w temperaturze pokojowej i podwyższonej materiałów podstawowych oraz złączy spawanych. Zweryfikowano zastosowane technologie spawania i oceniono przydatności badanych materiałów do określonych zastosowań.

EN

The paper presents characteristics of new creep resisting steels for boilers, and in particular the results of tests of thin- and heavy-walled welded joints. Low-alloy TIP23 and TIP24 steels, high-alloy T/P91, T/P92, VM12 and austenitic HR3C steels ivere subject to testing. Analysis of selection of the material for supercritical boiler steam superheater was conducted. Characteristics of the structure and mechanical properties at ambient and elevated temperature of basic materials and welded joints were presented. The applied technologies of welding were verified, moreover usability of the examined materials in specific applications was assessed.