Preparation of AlN-ZrO2(Ca) Composites by Hot Pressed Sintering

AlN-ZrO2 composites were prepared by hot pressed sintering with AlN particle (d≈2mm, d≈1.5mm and d≈1mm) and ZrO2 powder as material. Its phase composition, thermal conductivity and sintering performance were investigated by XRD, SEM, EDS and performance testing. The results showed that AlN could be reserved in samples, and the thermal conductivity and the apparent porosity of the samples ascended with increase of the content of AlN, and the bending strength of the samples with same AlN particle occurred change according to V-shape with content of AlN increasing. Thereinto, the thermal conductivity of the samples with 1.5mm AlN was most excellent, amang samples with AlN particle of 2mm, 1.5mm and 1mm, and sintering performance of the samples with 1mm AlN was best. Particle interface of AlN and ZrO2 was high concentration area of elements Ca and O, and was a structural loose crack area with CaAl12O19 formed. The area is abominable for performances of AlN-ZrO2 composites such as thermal conductivity, density and strength. It is more appropriate for preparation of AlN-ZrO2 composites with AlN particle of 1.5mm and 1mm as materials.