Resumen:

«Additive manufacturing processes are predominantly governed by complex thermomechanical interactions that critically influence the mechanical properties and the quality of the final product. This study first developed a mathematical framework of general small-strain thermo-mechanics that can incorporate an arbitrary elastic or inelastic material model. The framework was subsequently integrated into the MUESLI material library and the IRIS finite element code. The implementation was verified by simulating a benchmark problem. The results exhibited the expected influence of temperature-dependent material properties, highlighting their impact on the model predictions.

Furthermore, the Laser Powder Bed Fusion (LPBF) process, a common additive manufacturing technique for creating complex metal parts from a powder bed, was modeled with the developed temperature-dependent material. A test case was run with temperature-dependent material properties of a typical metal with representative process parameters.
The temperature and stress distribution results were found qualitatively realistic, and the trends were in agreement with the established thermomechanical principles. Moreover, a simplified Direct Energy Deposition (DED) process, an additive technique that simultaneously feeds and melts material to build or repair components, was modeled and implemented in IRIS. The model incorporated key physical phenomena, including material deposition, phase transformations, and heat transfer modes. A test case confirmed the model’s capability to adequately capture the development of residual stresses and associated mechanical deformations.

The initial results, while preliminary, demonstrate a functionally correct implementation and capture the expected thermomechanical trends.
This establishes a working foundation for the subsequent development and the incorporation of more complex physics in the future work.»