Effect of the heat treatment on the structure and properties of GX12CrMoVNbN9-1 cast steel

• Autorzy: Golański G.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The paper presents the influence of heat treatment parameters (austenitization and tempering temperature) on the microstructure and mechanical properties of high - chromium martensitic GX12CrMoVNbN9-1 (GP91) cast steel. Moreover, the influence of stress relief annealing at the temperatures of 730 and 750oC on microstructure and properties has been investigated. Design/methodology/approach: Microstructure of the cast steel was characterized using optical metallography and transmission electron microscopy. Identification of precipitates was made by means of thin foils and extraction carbon replicas. The size of precipitations was determined by Image Pro Plus software. Moreover, the mechanical properties (static tension, hardness and impact energy) have been tested. Findings: What has been determined is the influence of heat treatment parameters on microstructure and mechanical properties of GP91 cast steel. Heat treatment (hardening and high-temperature tempering) of GP91 cast steel allowed to obtain a fine-grained microstructure of high-tempered martensite with numerous precipitates whose properties met the standard requirements, regardless of the heat treatment parameters. Research limitations/implications: It is necessary to continue the research to determine description of the microstructure after different heat treatment parameters. Practical implications: Optimization of the heat treatment parameters from the aspect of using the investigated cast steel for long-term operation in power units designed for working at the so-called supercritical parameters. Originality/value: The relationship between the heat treatment parameters (austenitization and tempering temperatures) and mechanical properties of high - chromium martensitic GX12CrMoVNbN9-1 (GP91) cast steel was specified. Moreover, the influence of the stress relief annealing parameters on microstructure and properties has been shown.

Słowa kluczowe

EN

metallic alloys; mechanical properties; high-chromium martensitic cast steel; microstructure; precipitates

PL

stopy metaliczne; właściwości mechaniczne; stal martenzytyczna; stal wysokochromowa; stal węglowa; mikrostruktura; wydzielenia

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2010
• Tom: Vol. 46, nr 2
• Strony: 88--97
• Opis fizyczny: Bibliogr. 18 poz.

Twórcy

autor

Golański G.

• Institute of Materials Engineering, Częstochowa University of Technology, Al. Armii Krajowej 19, 42-200 Czestochowa, Poland,

Bibliografia

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