Thermo-mechanical simulation of track development in the Laser Beam Melting process - Effect of laser-metal interaction

Joint 5th International Conference on Advances in Solidification Processes;5th International Symposium on Cutting Edge of Computer Simulation of Solidification, Casting and Refining

土木建筑工程;计算机科学

Queva, Alexis^1^3 ; Mayi, Yaasin^2^3 ; Bellet, Michel^1 ; Guillemot, Gildas^1 ; Peyre, Patrice^2 ; Dal, Morgan^2 ; Moriconi, Clara^3 ; Metton, Charlotte^3

MINES ParisTech, PSL Research University, CEMEF - Centre de Mise en Forme des Matériaux, CNRS UMR 7635, CS 10207 rue Clause Daunesse, Sophia Antipolis Cedex

06904, France^1

PIMM Laboratory, UMR 8006 CNRS, Arts et Métiers ParisTech, 151 Bd de l'Hôpital, Paris

75013, France^2

Safran, Site de Paris-Saclay, Rue des Jeunes Bois - Chateaufort, CS 80112, Magny-les Hameaux

78772, France^3

关键词: Energy-efficient process;    Laser energy absorption;    Laser-matter interactions;    Laser-metal interactions;    Material absorption;    Solidification paths;    Thermodynamic database;    Thermomechanical simulation;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/529/1/012005/pdf
DOI  :  10.1088/1757-899X/529/1/012005

来源: IOP

【 摘 要 】

Interest has recently emerged for the manufacture of aeronautical parts by Laser Beam Melting (LBM) additive process. This energy efficient process can for instance be used to build complex geometries, which cannot be made with traditional processes. However, complex phenomena occur during powder melting and track development : vaporisation phenomena inuence laser-matter interaction by creating metal vapours that are responsible for the reduction of absorbed energy. The recoil pressure generated by the vaporisation counteracts the surface tension between the melt pool and the inert gas, also inducing liquid instabilities. The study of lasermatter interaction and induced phenomena can help understand the origin of defects such as porosities or cracks. In this approach, a level-set modelling of the LBM process at a mesoscopic scale is proposed to follow melt pool evolution and track development during build. A volume heat source model is used for laser/powder interaction considering the material absorption coefficient. A surface heat source is used to take into account the high laser energy absorption by dense metal alloys. An energy solver is coupled with thermodynamic database and pre-determined solidification path. Shrinkage during consolidation from powder to liquid and compact medium is modeled by a compressible Newtonian constitutive law. An automatic remeshing adaptation is also used to save time and avoid high computational cost. In the future, the computation of multiple beads or the build of a wall in a context of lattice structures will have to be considered.