Simulation of Carbide/Nitride Precipitation in 3%Cr1%Mo/P91 Steel Weldment At Temperature Range 700-575oC

JAN, Vít and Jiří SOPOUŠEK. Simulation of Carbide/Nitride Precipitation in 3%Cr1%Mo/P91 Steel Weldment At Temperature Range 700-575oC. In Thermodynamics of Alloys TOFA 2002. Roma: Universita di Roma "La Sapiensa", 2002, p. PO55, 1 pp.

Basic information

• Original name: Simulation of Carbide/Nitride Precipitation in 3%Cr1%Mo/P91 Steel Weldment At Temperature Range 700-575oC
• Authors: JAN, Vít (203 Czech Republic) and Jiří SOPOUŠEK (203 Czech Republic, guarantor).
• Edition: Roma, Thermodynamics of Alloys TOFA 2002, p. PO55, 1 pp. 2002.
• Publisher: Universita di Roma "La Sapiensa"

Other information

• Original language: English
• Type of outcome: Proceedings paper
• Field of Study: 10403 Physical chemistry
• Country of publisher: Italy
• Confidentiality degree: is not subject to a state or trade secret
• RIV identification code: RIV/00216224:14310/02:00006364
• Organization unit: Faculty of Science
• Keywords in English: DICTRA;ThernoCalc;phase;diffusion;CALPHAD
• Tags: CALPHAD, DICTRA, Diffusion, phase, ThernoCalc

Abstract

The study the relationships among the element redistributions, the microstructure at various positions across the weldments, and local mechanical properties represents the basic source for advanced design of stable welds of dissimilar alloys. The kinetics of phase transformations in diffusion-affected zone determine weld stability in many cases. The processes in welded joint of progressive steel P91 (8,5wt% Cr -0,88%Mo-0,23%V-0,045%N-0,1%C) and 3Cr1Mo electrode (2,73wt%Cr-0,96%Mo-0,12%C) were simulated using combination of CALPHAD method(1) and the same method as can be found in DICTRA programme(2, 3, 4) . The thermodynamic database STEEL11.TDB(5) and mobility database DIF12.TDB(6) were applied for the simulations of the weldments at long treatment . This two databases were developed in Brno and they are assessed for calculation of phase diagrams and the simulations of the weldments at temperatures about 500oC too. The equilibrium calculations using CALPHAD method allowed us to predict phase diagrams for both 3Cr1Mo and P91 steels. The diffusion and phase transformation processes occurred in 3Cr1Mo/P91 welded join were simulated using DICTRA programme. It enabled us to evaluate time-distance dependences for phase compositions and element redistribution in diffusion-affected zone at temperature range 700-575oC. This simulation results at different temperatures are complemented with experimental results. The most interesting results concern carbonitride, and high molybdenium carbide phase transformations. The described method can be used for weldments design.

Links

• GA106/00/0855, research and development project: Name: Kinetika precipitace karbidů v Cr-Mo ocelích

Investor: Czech Science Foundation, Kinetics of carbide precipitation in Cr-Mo steels