J 2004

Weld joint simulations of heat-resistant steels

SOPOUŠEK, Jiří, Vít JAN and Rudolf FORET

Basic information

Original name

Weld joint simulations of heat-resistant steels

Name in Czech

Simulace svarových spojů v žáropevných ocelích.

Authors

SOPOUŠEK, Jiří (203 Czech Republic, guarantor), Vít JAN (203 Czech Republic) and Rudolf FORET (203 Czech Republic)

Edition

Archives of Metallurgy and Materials, Warszawa - Krakow, Polish Academy of Sciences, 2004, 1733-349

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10403 Physical chemistry

Country of publisher

Poland

Confidentiality degree

není předmětem státního či obchodního tajemství

RIV identification code

RIV/00216224:14310/04:00011683

Organization unit

Faculty of Science

UT WoS

000224772200004

Keywords in English

phase profile carbon redistribution electrode weld DICTRA
Změněno: 22/11/2004 14:37, prof. RNDr. Jiří Sopoušek, CSc.

Abstract

ORIG CZ

V originále

Knowledge of microstructure stability is essential for reliable estimations of the lifetime limitations of materials and welded joints at higher temperatures. The CALPHAD method complemented with appropriate diffusion approach can help us to simulate phase and element profile evolutions inside diffusion-affected zone of weld joint. The different heat-resistant steels (alloying base: Cr, Ni, Mo, V, C, N) and their weld joints are objects of our study. The particular results of the equilibrium calculations are presented as phase diagram cross-sections and element activities of the selected heat-resistant steels. The carbon and nitrogen activity temperature dependences were calculated for individual steels. The difference in these activities in two different steels (at given temperature) indicates diffusion flow direction, which can be opposite then deduced from the element content (up-hill diffusion). The simulations respect the coexistence of different carbide phases in the materials and they are conducted on the assumption that local phase equilibrium holds and that diffusion is the control process of phase transformation. The phase diagram calculations and diffusion couple simulations involving time-distance dependences for phase and element redistributions in diffusion-affected zones enabled us to obtain basic information, which allow estimating thermodynamic and diffusion stabilities of the studied heat-resistant steels and their weld joints.

In Czech

metodou CALPHAD doplněnou o příslušný popis difúzně řízených dějů je simulován vývoj profilů chemického a fázového složení v žáropevných ocelích na bázi Fe, Cr, Ni, Mo, V, C, N a jejich svarech. Jsou presentovány predikce fázových diagramů, závislosti aktivity uhlíku a dusíku na teplotě a similované profiy. Obsah je doplněn o up-hill difúzi uhlíku.

Links

GA106/03/0636, research and development project
Name: Teoretické modelování a experimentální studium strukturní stability moderních žárupevných ocelí a jejich svarů