화학공학소재연구정보센터
Journal of the American Ceramic Society, Vol.100, No.2, 529-538, 2017
Minimum time heating cycles for diffusion- versus permeability-controlled binder removal from ceramic green bodies
A comparison of minimum time heating cycles (MTHCs) was conducted for binder removal from ceramic green bodies for two mass transfer mechanisms: diffusion and gas permeability. The MTHCs were determined by combining approximate analytic solutions to the governing reaction-diffusion and reaction-gas permeability equations with a variational calculus algorithm containing a constraint on pressure buildup within the green body. Both the temperature-time profile and duration of the MTHCs were sensitive to the operative transport process as well as to a number of model parameters including the pressure constraint, the total furnace pressure, the reaction kinetics, the gas permeability, and the diffusivity as described by the free volume theory. Strategies were identified which are most effective for decreasing the cycle time for each mass transfer mechanism.