3D printing of porous zirconia membranes by nanoparticle jetting

NanoParticle Jetting NPJ is a new material jetting process that builds ceramic membranes from zirconia nanoparticles embedded inside a liquid solvent that serves as a carrier. The advantage of the latest technology is the ability to deposit nanoparticles with a layer thickness of 10 mu m selectively and a jetting resolution of 20 mu m after sintering. The study evaluates the physical and mechanical properties and microstructure of NPJ-printed zirconia ceramic membranes. The experimental results indicate that NPJ-printed membranes exhibit a high relative density, smooth surface with a minor 0.33 mu m roughness, 14.5 % radial and 12 % axial shrinkage, Vickers hardness of 67.8 HRC before sintering and 75.6 HRC after sintering, low flexural strength of 0.5 MPa before and 11 MPa after sintering, dense grain distribution, and meandering pores 2.6 mu m width at the green body stage and 0.3 mu m after 3 hours sintering at 1550 degrees C.