The Role of the Apparent Density on the Permeability of Porous Stainless Steel Parts

Austenitic stainless steel filters are mostly used when there is an aggressive environment condition, especially when good corrosion and mechanical resistance at relatively high temperature are required. These filters are usually obtained from non-spherical, mostly atomized powders by cold pressing and sintering. In order to achieve an adequate performance concerning permeability, powders with a narrow range of particle size should be used. However, besides particle size distribution, apparent density of the selected powder, which can be adjusted by the particle size, shape and distribution, affects the performance of the final product. Particle size distribution, particle shape and particle surface roughness control apparent density. This work presents some results on the evaluation of such effect.