Selective-area laser deposition and selective-area laser-deposition vapor infiltration are two gas-phase solid-freeform techniques capable of the direct fabrication of arbitrary structures. The wide range of available gas precursors allows unique combinations of materials to be achieved in the final shape. Tailoring of the local microstructure can be achieved by carefully controlling processing temperature, gas partial pressure, and other variables. The versatility of the two techniques can be seen in the fabrication of a structure comprising multiple materials.

A 3D finite element model was developed that simulates selective area laser deposition vapor infiltration (SALDVI) of silicon carbide. The model predicts the laser input power history needed to maintain constant surface temperature and the distribution of vapor deposited SiC within the powder bed as well as on the surface of the powder bed. The model considers a moving Gaussian distribution laser beam, temperature‐ and pore‐dependent thermal conductivity, specific heat and temperature‐dependent deposition rate. Furthermore, the model also includes closed‐loop control of the laser power to achieve a desired target processing temperature on the surface of the power bed. Effects of laser scanning rates have been investigated. The simulated solid fraction and SALD distributions are also consistent in the trend with the experimental data.

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