Fabrication of the Tube-shaped SUS316L Gas Filter with the Double Layered Pore Structures by Wet Powder Spraying Process

In this study, the SUS316L gas filter having double layered pore structures was fabricated and pore characteristics were analyzed after coating spherical powder and flake-shaped powder on a tube-shaped pre-sintered SUS316L support using a wet powder spraying (WPS) process. In the WPS process, slurry composed of metal powder, solvent, and binder is sprayed onto the surface of a support tube with a single coarse pore structure. The powder used in the fine pore structure layer was mixed with flake-shaped and sphere-shaped powder in ratios of 3:1, 1:1, and 1:3, respectively. In order to increase the uniformity of the filter surface structure, the surface of the filter was rolled after sintering and the resulting microstructure was analyzed. The thickness of the manufactured gas filter having double pore structure was checked through OM and porosity was measured using the Image analysis program. In addition, air permeability was measured using gas permeameter.