Ceramic material, powder and layer system
An improved ceramic material for heat insulation is achieved by the following selection of specific stabilizers and the adapted proportions: Base of zirconium dioxide (ZrO 2 ) with: 1.0 wt. % to 9.0 wt. % of base stabilizers: yttrium oxide (Y 2 O 3 ), hafnium oxide (HfO 2 ), wherein at least yttrium oxide (Y 2 O 3 ) is used, and at least one of the additional stabilizers: erbium oxide (Er 2 O 3 ) and/or ytterbium oxide (Yb 2 O 3 ) with a proportion of 0.2 wt. % to 20 wt. %.
1 . A ceramic material based on zirconium oxide (ZrO 2 ), comprising (in wt %):
up to 8.0 wt % of base stabilizers, the base stabilizers comprising:
at least 2.5 wt % yttrium oxide (Y 2 O 3 ), and optionally hafnium oxide (HfO2),
additional stabilizers comprising:
erbium oxide (Er 2 O 3 ) and/or ytterbium oxide (Yb 2 O 3 )
with a fraction of 0.2 wt % to 20.0 wt %,
further comprising:
aluminum oxide (Al 2 O 3 ) 0.1%-3.0 wt %
and further comprising allowed impurity levels:
calcium oxide (CaO)
up to 0.2 wt%,
iron oxide (Fe 2 O 3 )
up to 0.2 wt%,
magnesium oxide (MgO)
up to 0.2 wt%,
silicon oxide (SiO 2 )
up to 0.3 wt%,
titanium oxide (TiO 2 )
up to 0.2 wt%.
2 . The ceramic material as claimed in claim 1 , comprising the hafnium oxide (HfO 2 ).
3 . The ceramic material as claimed in claim 1 , wherein the yttrium oxide (Y 2 O 3 ) is the only base stabilizer.
4 . The ceramic material as claimed in claim 1 ,
wherein the yttrium oxide (Y 2 O 3 ) content is 2.5 wt % to 5.5 wt %.
5 . The ceramic material as claimed in claim 1 ,
comprising the hafnium oxide (HfO 2 ), wherein the hafnium oxide (HfO 2 ) content is >2.0 wt % to 4.0 wt %.
6 . The ceramic material as claimed in claim 1 ,
comprising the hafnium oxide (HfO 2 ), wherein the hafnium oxide (HfO 2 ) content is 0.2 wt % to <2.0 wt %.
7 . The ceramic material as claimed in claim 1 ,
wherein the aluminum oxide (Al 2 O 3 ) content is 0.2 wt % to 1.5 wt %.
8 . The ceramic material as claimed in claim 1 , comprising
wherein the aluminum oxide (Al 2 O 3 ) content is 1.5 wt % to 3.0 wt %.
9 . The ceramic material as claimed in claim 1 ,
wherein the ytterbium oxide (Yb 2 O 3 ) is the only additional stabilizer.
10 . The ceramic material as claimed in claim 1 ,
wherein the erbium oxide (Er 2 O 3 ) is the only additional stabilizer.
11 . The ceramic material as claimed in claim 1 , which comprises as the additional stabilizers the ytterbium oxide (Yb 2 O 3 ) and the erbium oxide (Er 2 O 3 ).
12 . The ceramic material as claimed in claim 1 , consisting of
13 . The ceramic material as claimed in claim 1 , consisting of
14 . The ceramic material as claimed in claim 1 ,
comprising the ytterbium oxide (Yb 2 O 3 ), wherein the ytterbium oxide (Yb 2 O 3 ) content is 5.5 wt % to 8.5 wt %.
15 . The ceramic material as claimed in claim 1 ,
comprising the erbium oxide (Er 2 O 3 ), wherein the erbium oxide (Er 2 O 3 ) content is 2.0 wt % to 4.0 wt %.
16 . The ceramic material as claimed in claim 1 ,
comprising the erbium oxide (Er 2 O 3 ) and the ytterbium oxide (Yb 2 O 3 ),
comprising (8.0−x) wt % of Y 2 O 3 +[(2-4)*x] wt % of Yb 2 O 3 /Er 2 O 3 , and
where x represents a weight fraction of the additional stabilizers.
17 . A ceramic powder comprising,
a composition of a material as claimed in claim 1 .
18 . A layer system at least comprising
a metallic substrate,
optionally a metallic adhesion promoter layer, and
at least one ceramic layer comprising the ceramic material as claimed in claim 1 .
19 . The layer system as claimed in claim 18 , comprising
a NiCoCrAlY based metallic adhesion promoter layer between the ceramic layer and the metallic substrate, and
optionally comprising silicon (Si), rhenium (Re) and/or tantalum (Ta).
20 . The layer system as claimed in claim 18 ,
wherein below the ceramic layer there is a ceramic sublayer comprising the ceramic material, which is at least 20% thinner in configuration.