A comparison was made of the sensitivity, of estimates of the bulk elastic modulus of the M–H system, and the diffusion coefficient of H. These were deduced from 3 alternative transfer functions for H transport through a thin metal membrane. The comparison was performed with respect to the uncertainty in the equilibrium concentration of H, its partial molar volume and the thickness of the specimen. In most cases, the estimate of the elastic modulus was more sensitive to these uncertainties than was the estimate of the diffusion coefficient. The effects of uncertainty in the partial molar volume were of utmost importance. However, in the case of relatively small H concentrations, the uncertainty in the specimen thickness was most important for the estimation of the elastic modulus as acquired from a one-port flux transfer function. The estimates of both parameters, as acquired from the concentration transfer function, were unaffected by the present uncertainties. However, other factors decided that, for practical use, the one-port flux transfer function was the most adequate.

Sensitivity of Transfer Functions of Transport of Hydrogen in Elastic Metals to the Uncertainty of their Parameters. P.Zoltowski: Acta Materialia, 2003, 51[18], 5489-97