Development of Si3N4 based material for diesel particulate filter application with carbothermal reduction and nitridation method

In this thesis, in order to full fill the environmental emissions needs new diesel particulate filter materials and new production processes developed. There are several filter material exist in the DPF market. Porous Si3N4 investigated considering the performance and structural properties. Carbothermal reduction and nitridation of silicon nitride(CRNSN) method and reaction bonding(RBSN)method combined. C/SiO2 ratio, quantity of Si3N4 additive, effect of starting raw materials and sintering additives type determined and porous silicon nitride filters produced. Pressure drop tests, permeability and soot loading tests made to the developed porous Si3N4 Ceramic filter. With using this two method, mechanical and filtering properties of porous silicon nitride developed with acceptable cost. Regarding the experimental work, pore size and distribution are more important than porosity volume. Pore size and distribution directly related with the filter performance. Microstructure is key point of the mechanical properties. Even though produced porous Si3N4 has low permeability, high soot loading properties obtained.