An investigation upon overhang zones by using finite element modelling and in-situ monitoring systems

The characteristic of heat transfer in direct metal laser sintering is a key point in terms of overall material properties. Thus, this research focuses on the temperature distribution in overhang zones of Inconel 625 by employing finite element modelling and in-situ monitoring systems. The larger fluctuations in radiation signals are observed during solidification of melt pools. Furthermore, optical tomography confirms that overheating caused by lack of heat transfer between melt pool and powder occurs in overhang regions. This phenomenon is explained by finite element modelling based on thermal behavior of melt pool with powder, and surface characterization.