Zirconia Toughened Alumina | Al<sub>2</sub>O<sub>3</sub>/ZrO<sub>2</sub>

Zirconia Toughened Alumina | Al₂O₃/ZrO₂

Zirconia Toughened Alumina has improved bending strength and higher reflectivity than alumina and AlN. These qualities combined with good heat dissipation means that they are ideal for LED package and power module for automotive and sustainable energy technologies.

Material Characteristics for Alumina Substrates (Al₂O₃), Zirconia Toughened Alumina Substrates ( Al₂O₃/ZrO₂), Aluminium Nitride Substrates (AlN), and Silicon Nitride (Si₃N₄)

		Condition	Unit	Al₂O₃					Al₂O₃/ZrO₂		AlN	Si₃N₄
		Condition	Unit	AS970	HA-96-2	HBS	HRA	HA-996	ZTA	HRZ	AN-170	SN-90
Material		-	-	96.5%	96%	96.5%	96%	99.6%	Al₂O₃/ZrO₂	Al₂O₃/ZrO₂	AlN	Si₃N₄
Color		-	-	White	White	White	White	White	White	White	Gray	Gray
Bulk density		-	g/㎤	3.74	3.75	3.75	3.60	3.90	4.00	3.85	3.30	3.22
Surface roughness Ra		-	µm	0.4	0.4	0.3	0.3	0.1	0.2	0.2	0.2	0.4
Reflectivity		0.3-0.4mmt	%	70	70	70	85	75	80	87	35	-
Reflectivity		0.8-1.0mmt	%	80	80	80	95	85	90	97	25	-
Mechanical	Bending strength	3-point method	MPa	450	400	500	370	470	700	550	450	800
	Modulus of elasticity	-	GPa	330	330	330	-	330	310	-	320	310
	Vickers hardness	-	GPa	14	14	14	-	16	15	14	11	15
	Fracture toughness	IF method	MPa･m^1/2	3.0	3.0	-	-	-	3.5	-	3.0	6.5
Thermal	Coefficient of thermal expansion	40-400°C	10^-6/K	6.7	6.7	6.7	6.7	6.8	7.1	7.1	4.6	2.6
	Coefficient of thermal expansion	40-800°C	10^-6/K	7.8	7.8	7.8	7.8	7.9	8.0	8.0	5.2	3.1
	Thermal conductivity	25°C	W/(m･K)	24	24	24	20	29	27	23	180	85
	Thermal conductivity	300°C	W/(m･K)	12	12	12	-	13	16	-	120	-
	Specific heat	25°C	J/(㎏･K)	750	750	750	750	780	720	720	720	680
Electrical	Dielectric constant	1MHz	-	9.8	9.8	9.8	-	9.9	10.2	-	8.5	7.8
	Dielectric loss factor	1MHz	10^-3	0.2	0.2	0.2	-	0.2	0.2	-	0.3	0.4
	Volume resistivity	25°C	Ω･㎝	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴	>10¹⁴
	Breakdown strength	DC	㎸/㎜	>15	>15	>15	>15	>15	>15	>15	>15	>15