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In Laser Power Bed Fusion (LPBF), the process and operating parameters influence the mechanical and geometrical characteristics of the manufactured parts. Therefore, the optimization and control of these parameters are mandatory to improve the quality of the produced parts. During manufacturing, the process parameters are usually constant whatever the part size or the built layer. With such settings, the manufacturing process may lead to an inhomogeneous thermal behavior and locally overheating areas, impacting the part quality. The aim of this study is to take advantage of an analytical thermal model to modulate the laser power upstream of manufacturing.

The approach takes place in two steps: the first step consists in calculating the preheating temperature at the considered point and the second one determines the power modulation of the laser to reach the desired temperature at this point.

Numerical investigations on several use cases show the effectiveness of the method to control the overheated areas and to homogenize the simulated temperature distribution.

The specificity of this model lies in its ability to directly calculate the amount of energy to be supplied without any iterative calculation. Furthermore, to be as close as possible to the technology used on LPBF machines, the kinematic behavior of the scanning head and the laser response time are also integrated into the calculation.

This paper aims to propose an analytical thermal three-dimensional model that allows an efficient evaluation of the thermal effect of the laser-scanning path. During manufacturing by laser powder bed fusion (LPBF), the laser-scanning path influences the thermo-mechanical behavior of parts. Therefore, it is necessary to validate the path generation considering the thermal behavior induced by this process to improve the quality of parts.

The proposed model, based on the effect of successive thermal flashes along the scanning path, is calibrated and validated by comparison with thermal results obtained by FEM software and experimental measurements. A numerical investigation is performed to compare different scanning path strategies on the Ti6Al4V material with different stimulation parameters.

The simulation results confirm the effectiveness of the approach to simulate the thermal field to validate the scanning strategy. It suggests a change in the scale of simulation thanks to high-performance computing resources.

The flash-based approach is designed to ensure the quality of the simulated thermal field while minimizing the computational cost.

To satisfy the demands for rapid prototyped small‐size objects with intricate microstructures, a high‐resolution stereolithography (SL) system is developed.

This novel SL system consists of a single mode He‐Cd laser, an improved optical scanning system, a novel recoating system and a control system. The improved optical system consists of a beam expander, an acoustic‐optic modulator, a galvanometric scanner and an F‐θ lens; the recoating system consists of roller pump, resins vat with an integrated high‐resolution translation stage and part building platform and a scraper. Experimental studies were performed to investigate the influences of building parameters on the cured line width and depth.

With the SL system, a laser light spot with a diameter of 12.89 μm on the focal plane and resin layers with a thickness of 20 μm have been obtained. The experimental results indicate that cured depth and width increase with the ratio of laser power to scanning speed, and cured line with a width of 12 μm and a depth of 28 μm was built, which showed the capability building microstructures with this new SL system.

The building area limited to 65 × 65 mm, is smaller than that of current SL system.

Small objects with intricate microstructures can be fabricated with the SL system.

The high‐resolution SL system provides a solution to the problem that has hampered the progress of SL process into a high resolution ranges below 75 μm.