Fabrication of multilayer 316L/PSZ gradient composite pipes by means of multi-billet extrusion

Multilayer metal-ceramic gradient composite pipes were extruded through simultaneous extrusion of different types of particulate pastes composed of different proportions of stainless steel (316L) to partially yttria-stabilized zirconia (PSZ) with binder by means of multi-billet extrusion, then were solidified utilizing gas-pressure sintering. The multilayer composite pipes have sound transitional boundaries between adjacent layers. Because of the composition gradient, transitional boundaries between adjacent layers possess good bonding, and no interfacial decohesion occurs during flexural and compressive loading, which shows relatively high bonding strength between adjacent layers. In summary, multilayer metal-ceramic gradient composite pipe with good interfacial bonding between adjacent layers can be fabricated utilizing multi-billet extrusion and sintering.