RESEARCH PROGRAM

Title: Numerical Simulation of the Additive Manufacturing Processes

 

Name: Daobo Zhang

E-Mail: dzhang@rhrk.uni-kl.de

Phone: 0631-205-2127

 

 

Project description:

 

Starting situation

Additive manufacturing (AM) has been widely applied to fabricate parts in various industries due to its substantial benefits compared to conventional machining. Over the previous decades, a significant number of different AM processes have been developed in which parts

are manufactured by adding material in layers. However, the final pieces produced using the AM processes often do not fulfill the mechanical performance requirements or exhibit

difficulty in predicting distortion behavior, mainly due to the presence of thermally induced residual stresses and distortion. Thus, predicting and controlling residual stresses and distortion is vital to improve the mechanical properties and dimensional accuracies to the final part. To this end, the numerical methods are utilized.

 

 

Approach

A particle finite element method (PFEM) is applied to simulate laser-based additive manufacturing processes in the macro-scope, which involve a weakly coupled thermalmechanical problem. Therefore, for the temperature field, the gaussian distribution heat source model will be used. Also, thermal conduction, convection, and radiation will be taken into account. For the mechanical field, Von Mises plasticity with linear isotropic hardening will be included. In addition, the phase change and temperature-dependent material properties will be modeled as well.

 

Expected Results

A numerically stable model of the laser-based AM process will be developed. The model can provide an accurate prediction of the temperature variation with time, the residual stresses, and distortion. Consequently, it will improve the mechanical properties of the final part by optimizing progress parameters.