Research on preparation and characterization of Ti-Ti5Si3 gradient composite porous material via in-situ reactive process

•Ti-Ti5Si3 gradient composite porous material was fabricated via in-situ reactive process.•The Ti5Si3 phases of porous membrane were confirmed by XRD and XPS.•The synthesized granules on the porous membrane is well distributed with the size of ∼1.0 µm.•There are two distinct layers observed in the membrane prepared by fine powder Gradient composite porous material can reach a high filtering accuracy with larger filtration flux, and the filter elements applied in separation equipment can enhance the filtration efficiency and reduce the energy consumption. Ti-Ti5Si3 gradient composite porous material was successfully prepared by in-situ reaction process with the raw materials of Ti powder and high purity quartz tablets. Microstructures and filtration properties prepared under different synthesized conditions have been studied, including the parameters of pressure sintering (additional loads and temperatures) and powder particle sizes. The synthesized granules on the membrane are well distributed with the size of ∼1.0 µm, and the thickness of the membrane is 3.0∼6.3 µm. The relative air permeability coefficient of porous membrane reduces raptly compared to the sample matrix due to the decrease of pore size. The all synthesized membranes show the presence of Ti and Ti5Si3 phases. There are two distinct layers observed in the membrane layers prepared by fine powder due to in-situ over-reaction.