Sub-Micro Particle Matter Detection for Metal 3-D Printing Workshop

The metal powder as one kind of 3-D printing material is easy to diffuse into the air and suspend in the air in a long period because of its small size. Evidences show that particles with an aerodynamic diameter of less than 1.0 µm seriously threaten human health because they can get deep into your respiratory and bloodstream system easily with the size decreasing. The conventional monitors for this fine-particle detection are either bulky or lack of accuracy in sub-micro particle detection. In this paper, we report a novel particle sensor for sub-micro, even nanoscale, particle detection. The particle sensor is based on an optical method in which an ultra-large collecting angle of scattered light is achieved by a complicated parabolic collector, and the final shape of core optical component is a cylinder with a dimension of 11 mm (height) × 25 mm (diameter). The testing results are consistent with the simulation results based on the Rayleigh scattering and Mie scattering theory model. Finally, the resolution of the particle sensor is around 7.9 µg/m3. It can be adopted by the applications of particle concentration detection in metal 3-D printing workshop.