Zirconia

Material		Alumina Al2O3				Zirconia ZrO₂			Mixed oxides ZrO₂/Al₂O₃			Silicon carbide SIC			Silicon nitride Si3N4	Boron nitride	Metal
						ATZ	ZTA
Brief description		Al2O3 purity 96%	Al₂O₃ purity 99.7%	Mg-PSZ MgO partially stabilized	Y-TZP Y₂O3 partially stabilized	ZrO₂ particle-reinforced	Al₂O₃ particle-reinforced	SiSiC Si-infiltrated with 8-12% free Silicon	SSiC sintered without free silicon	HP SIC hot-pressed without free silicon	HP SN hot-pressed	SSN sintered	HP BN* hot-pressed	C-15* plain steel
Color		white	white	yellow	white	white	white	black	black	black	black	grey	white	-
Structural properties
Density	g/cm³	3.7	3.9	5.7	>6.0	5.5	4.1	3.1	3.1	3.2	3.2	3.22	2	7.87
Open porosity	%	0	0	0	0	0	0	0	0	0	0	0	0	0
Average crystal size	µm	10	5	50	0.7	0.7	0.5	15	1	10	5	5	-	-
Mechanical properties
Vickers hardness (HV₁₀)	MPa	1400	1800	1200	1300	1400	1700	2200	2500	2500	1600	1450	190	700
Compressive strength	MPa	2800	2800	1600	2200	2100	2600	1200	2200	2900	2500	2500	160	1000
Flexural strength	MPa	290	340	500	1000	820	600	320	420	430	850	750	70/30**	450
Fracture toughness	MPam^½	-	4.3	7.0	10.5	7.0	7.0	-	3.2	3.2	6.0	7.0	-	-
Elastic modulus*	GPa	350	380	200	200	220	360	350	410	440	320	300	30/25**	210
Weibull modulus*	-	10	10	12	20	20	20	12	10	12	18	15	-	-
Poisson's ratio*	-	0.22	0.22	0.3	0.3	0.27	0.24	0.22	0.17	0.16	0.26	0.25	0.13	0.33
Thermal properties
max. Application temperature* under protective gas	°C	1600	1650	900	1200	1200	1000	1350	1800	1800	1300	1300	2400	400
max. Application temperature* in air	°C	1600	1650	900	1200	1200	1000	1350	1500	1500	1100	1100	850	300
Specific heat at 20°C	J/Kg K	900	900	550	500	600	700	950	650	1000	750	700	-	462
Thermal conductivity at 100°C	W/mK	25	30	2	2	6	25	85	75	90	35	35	35	50
Coefficient of thermal expansion(20°C - 1000°C)	10^-6K^-1	8.5	8.5	10.5	10.5	9	9	4.5	4.1	4.1	3.2	3.3	2.2	11
Thermal shock resistance*	K	180	190	260	300	300	250	400	350	450	400	450	-	-
Electrical properties
Volume resistivity at 20°C	Ωcm	10¹⁴	10¹⁴	10¹⁰	10⁹	10⁹	10⁹	0.2	10-100	10²	10¹⁰	10¹²	10¹⁴	0.0015
Volume resistivity at 400°C	Ωcm	10¹¹	10¹²	10⁴	10⁴	10⁴	10⁷	-	-	-	-	-	-	-
Volume resistivity at 1000°C	Ωcm	10⁴	10⁷	10³	10³	10²	10⁵	0.05	0.2	0.2	10⁷	10⁷	10⁹	-
Dielectric strength	kV/mm	>18	>25	-	-	-	-	-	-	-	-	-	39	-
Dielectric constant at 20°C and 1 GHz	-	8	9	>20	>20	>20	-	-	-	-	20	20	-	-
Dielectric loss factor (tgΔ) at 20°C and 1 GHz	-	5x10^-4	2x10^-4	-	-	-	-	-	-	-	-	-	-	-
Dielectric loss factor (tgΔ) at 20°C and 10 kHz	-	3x10^-4	1x10^-4	-	-	-	-	-	-	-	5x10-2	5x10-2	-	-

Zirconia

The thermal insulator with mechanical high-performance properties

Zirconia offers the highest flexural strength, fracture toughness, thermal expansion and the lowest thermal conductivity of all oxide ceramics. Its thermal expansion is similar to that of steel, which has a positive effect on force-locked connections with metal parts thus reducing thermal stresses. These properties make zirconia a popular construction material for design engineers.

Specific properties
Applications

Specific properties

Low thermal conductivity (good thermal insulator)

Maximum flexural strength

Very high fracture toughness

High thermal expansion (similar to steel or cast iron)

Elastic modulus similar to that of steel

Very good tribological properties

High surface quality

Applications

Dental ceramics

Nozzles

Dosing bushings and pistons

Drawing and forming tools

Setting rings

Positioning pins

Zirconia

The thermal insulator with mechanical high-performance properties

Specific properties

Applications

CERTIFICATION - ISO 9001:2015

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