Study on Regional Continuous Energy Control Scanning Method for Selective Laser Melting

doi:10.3901/JME.2024.01.159

Abstract

Abstract: Aiming at the forming quality problems such as warpage and dross in the overhanging structural parts formed by selective laser melting (SLM), the solidified solid and powder in the forming process are studied based on the heat transfer difference in local area and the heat transfer between layers. The effect of the distribution on the temperature distribution to optimize the forming of the drape. An energy regulation optimization model driven by part geometric information is established. By identifying the geometric features of the model, the energy impact factor is calculated according to the proportion of solidified solids and material powder in the local area, and the localization of variable process parameters based on software adaptive adjustment is realized. Quantitative scanning, and finally realize the continuous regulation of regional energy and process optimization. A typical overhanging part is selected for 316L material printing experiment as a verification. The results show that compared with the unoptimized ordinary scanning scheme, the optimized scanning scheme based on software automatic energy regulation can improve the forming quality of overhanging structural parts with an inclination angle of less than 45°, and the forming quality of 40° When suspending structural parts, the Sa (Surface Average Roughness) of the suspending surface formed with variable parameters reaches 24.03 μm, which is 46.32 μm compared with the Sa formed with fixed parameters, and the surface finish is significantly improved; at the same time, it can be formed with a span of 8 mm horizontal overhang without support.

Key words: selective laser melting, overhang structure, energy control, scan strategy, fabricating quality

CLC Number:

TG665

QIN Lin, ZHANG Lichao, WANG Senlin, TANG Mingkai, SHI Yusheng. Study on Regional Continuous Energy Control Scanning Method for Selective Laser Melting[J]. Journal of Mechanical Engineering, 2024, 60(1): 159-169.

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