Erosion wear of laminated ceramic nozzles

SiC/(W,Ti)C ceramic nozzles with laminated structures were produced by hot pressing in order to reduce the tensile stress at the entry and exit region of the nozzle. Finite element method was used to evaluate the residual stresses due to the different thermal expansion coefficients and shrinkage of the SiC and (W,Ti)C solid–solution during the sintering process of the composite. The erosion wear of the laminated ceramic nozzle was assessed by sand blasting; the results were compared with those obtained with an unstressed reference nozzle with the same composition. The experimental results have shown that the laminated ceramic nozzles have superior erosion wear resistance to that of the homologous stress-free nozzles.