Enhancement of Densification and Thermal Conductivity in AlN Ceramics by Addition of Nano‐Sized Particles

Abstract

The effect of addition of nano‐sized particles on densification and thermal conductivity of AlN ceramics was investigated. The commercially available AlN powder (∼0.9 μm) was mixed with 1.89 mass% nano‐sized AlN particles (<0.1 μm), 3.53 mass% Y2O3, and 2.0 mass% CaO as sintering aid. The mixture was fired at 1500° and 1600°C in a tungsten resistance furnace under flowing N2 atmosphere. The results showed that a fully densified specimen was obtained at the lower temperature of 1600°C by addition of nano‐sized particles. The thermal conductivity of the resulting product was 133 W/m°C. The value is much higher than the 52 W/m°C for the sample prepared without adding the nano‐sized AlN powder. This study indicates a strong potential for the use of nano‐sized particles as additives in the densification of AlN ceramics.

Theory of Thermal Conductivity of Micro- and Nano-structured Materials

“…Qiu et al [23] added AlN nano-sized particles to the mixture of Y 2 O 3 , CaO and commercially available ceramic powder. Two different nano-scale processing schemes have been adopted.…”

Electrical and thermal properties of SiC–AlN ceramics without sintering additives

“…SiC ceramics show better mechanical properties, excellent oxidation and corrosion resistances at high temperatures, but relatively poor electrically insulating properties [1][2][3][4][5][6][7][8][9][10]. In contrast, AlN ceramics exhibit generally higher thermal conductivity and better electrically insulating properties but relatively poor mechanical properties [11][12][13][14][15][16][17]. It is well known that AlN and SiC form solid solutions with a wide range of compositions [18][19][20][21].…”

Thermal properties of polycrystalline cubic boron nitride sintered under high pressure condition

“…As a result, the low density materials with high thermal conductivity and low thermal expansion coefficient (matching to that of silicon) are extremely needed for reliable performance of electronic devices [1,2]. Non-metallic materials has attracted enough attention due to its excellent thermal properties and chemical stability, such as diamond [3,4], cubic boron nitride (cBN) [5][6][7], aluminum nitride (AlN) [8,9], silicon nitride (Si 3 N 4 ) [10,11], silicon carbide (SiC) [12,13], etc.…”