Using Simulation to Model Metallic Additive Manufacturing Processes

Additive Manufacturing (AM), widely known as 3D printing, is a direct digital manufacturing process, where a component can be produced, layer by layer, from 3D digital data with no or minimal use of machining, molding, or casting. AM has developed rapidly in the last 10 years and has demonstrated significant potential in cost reduction of performance-critical components. This can be seen through improved design freedom, reduced material waste, and reduced post-processing steps.

Modeling AM processes not only provides important insight into competing physical phenomena that lead to final material properties and product quality, but also provides the foundation to exploit the design space towards functional products and materials. The length and timescales required to model AM processes and to predict the final workpiece characteristics are very challenging.

Models also have to deal with multiple physical aspects, such as heat transfer and phase changes, as well as the evolution of material properties and residual stresses throughout the build time. The modeling task is therefore a multi-scale, multi-physics endeavor calling for a complex interaction of multiple algorithms.

ESI has developed a complete suite of tools addressing heat source/feed stock interaction in order to identify small-scale defects and residual stress. The solution offers distortion tools that reliably and efficiently predict the workpiece behavior during the build process as well as after its release from the base plate. The tools are integrated in a unified Integrate Computational Material Engineering platform (ICME): ESI-Additive Manufacturing.

The components of ESI-Additive Manufacturing have undergone several verification and validation studies. The results have been published in peer reviewed conferences and journal papers. The papers address modeling challenges related to both powder bed and blown powder processes. The results achieved include:

  • Powder distribution
  • Powder temperatures
  • Melt pool shape and dimensions
  • Consolidated material porosity
  • Surface roughness
  • Residual stresses
  • Distortion during build process and after release