Comprehensive predictive modeling and parametric analysis of multi-track direct laser deposition processes

Abstract

Laser direction deposition is a very useful method of fabricating complex parts directly from CAD drawings. Despite its usefulness, many parameters that affect the final quality of the fabricate part make the selection of optimal operating conditions difficult. The supplying powder jet conditions in a direct deposition process greatly influence the quality and property of deposition products. In this paper, new comprehensive numerical modeling is presented to predict the powder flow including temperature distribution, velocities and powder distribution and molten behavior during laser direct deposition in terms of various operating parameters. The model is capable of predicting the powder stream structure and multi-particle phase change process with liquid fraction evolution throughout the entire process with consideration of the particle morphology and size distribution in real powder samples. The model is also capable of predicting molten pool shape, heat affected zone and final deposition track height and width accurate during multi-track laser deposition. In addition, an experimental parametric study on various operating parameters on the final quality is presented.Laser direction deposition is a very useful method of fabricating complex parts directly from CAD drawings. Despite its usefulness, many parameters that affect the final quality of the fabricate part make the selection of optimal operating conditions difficult. The supplying powder jet conditions in a direct deposition process greatly influence the quality and property of deposition products. In this paper, new comprehensive numerical modeling is presented to predict the powder flow including temperature distribution, velocities and powder distribution and molten behavior during laser direct deposition in terms of various operating parameters. The model is capable of predicting the powder stream structure and multi-particle phase change process with liquid fraction evolution throughout the entire process with consideration of the particle morphology and size distribution in real powder samples. The model is also capable of predicting molten pool shape, heat affected zone and final deposition track height ...