Caractérisation mécanique de mousses céramiques pour la filtration des émissions Diesel

Mechanical characterization of ceramic foams for diesel exhaust gases filtration

¹ Dipartimento di Scienza dei Materiali ed lngegneria Chimica, Politecnico di Torino (I)
² LMCTS, U.R.A. CNRS 320, Université de Limoges (F)

Abstract

The potential of open-pore mullite foams for application in Diesel particulate filtration is under investigation, as substitute of the present cordierite honeycomb structures which have demonstrated limited durability due to the interaction between cordierite and some oxide pollutants at the high regeneration temperatures. Ceramic foams can be prepared by coating of an organic sponge with mullite slurries and subsequent sintering. Poly (urethane) sponges having different pores per inch values (ranging between 32 and 48 p.p.i.), adequate for this application, were used as starting materials and the resultant mullite foams were sintered at 1550°C for 3 hours. Due to the shrinkage associated with the sintering step, the final p.p.i. number of the ceramic sponges ranged between 45 and 65 p.p.i.. The mechanical response of these foams as Young's modulus, flexural and compressive strengths was evaluated on cubes and bars and compared with the literature data. The mechanical performances are acceptable for this kind of highly porous materials and for the forecast application.