Journal of Dental Research, Vol 64, 1337-1344, Copyright © 1985 by International & American Associations for Dental Research Online Journals
Analysis of alloy-porcelain compatibility using a multi-component material strip equation
P. H. DeHoff and K. J. Anusavice
An analytical model has been developed to calculate residual stresses and
curvature changes due to thermal contraction differences in metal-porcelain
strips consisting of any number (n) of component materials. This model was
also used to analyze transient and residual stresses due to solidification
of a semicircular arch casting. Results obtained from this model were in
close agreement with those obtained from finite element calculations for
the cases studied. Some experimental evidence exists to suggest that
thermal contraction coefficients of certain body porcelains progressively
increase with the number of firing cycles. Therefore, a parametric study
was conducted to determine the effects of variations in the thermal
contraction coefficient of each porcelain layer on residual stresses and
gap changes produced in porcelainized semicircular arch specimens. Based on
the analytical model developed in this study, we found that calculated
residual stresses near interfacial areas of adjacent layers of porcelain
are most sensitive to variations in thermal contraction coefficients of the
material layers.
