Thin ZrO2-films have been deposited on stainless steel substrates by a
sol-gel deposition process based on zircon-tetra-n-propoxide. Various
heat treatments were carried out. The comparison between the expected
film thickness determined by coating mass and the real film thickness
measured by ball cratering method indicates a porosity of 40 to 50 vo
l.% for rapidly annealed films. Films heated at a heating rate of 0.5
K/min show only a low porosity. X-Ray diffraction measurements were ca
rried out in order to examine the crystallization behavior of these fi
lms as a function of annealing parameters. An interesting correlation
between heating rate and crystallization was found and is explained by
the temperature dependence of nucleation rate and crystal growth. Cry
stallite sizes and microstrains were determined by peak profile analys
is. The crystallite sizes of the metastable cubic zirconia range betwe
en about 13 nm up to about 20 nm. X-Ray residual stress measurements i
ndicate a close correlation between the observed phase transformation
and the residual stress formation. (C) 1997 Elsevier Science S.A.