| 2005 №07 (01) | 2005 №07 (03) |
The Paton Welding Journal, 2005, #7, 8-13 pages
FE-modelling of the thermometallurgy and stress-distortion behaviour during PTA hardfacing
U. Semmler, K. Alaluss, K.-J. Matthes
Institute of Manufacturing and Welding Technology, University of Technology, Chemnitz, GermanyAbstract
The paper deals with the process of plasma transferred arc (PTA) deposition of thick hardfacing layers (vanadium-based alloys V12 and V18) on the base material (structural steel S355J0). The differences in the thermo-mechanical properties, local thermo-plastic deformations and phase transformations may cause high residual stress and distortion. The transient thermo-elastic-plastic behaviour of the PTA material deposition is investigated by means of the 3D Finite Element Method (FEM). All thermo-mechanical parameters are dependent on the temperature. The simulated results are compared with measurements of temperature distribution and distortions in order to increase the quality of the numerical models. Using the verified and improved FE-models one can study the influence of welding parameters on the deformations and residual stresses with the aim to optimize the weldments. For thick deposit layers the austenite-martensite transformations have a significant influence on the residual stresses and distortions. Technical applications are shown.
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