Grain size reduction in cemented carbides leads to higher mechanical properties. Therefore, preventing the grain growth during sintering is a crucial task. This study proposes the application of Al2O3 coatings obtained by atomic layer deposition (ALD) on WC-8Co powder, where Al2O3 is added as a grain growth inhibitor. After deposition, the films were found both on separate particles and on the dense agglomerates. The thickness of aluminum oxide varied in the range of 30-100 nm depending on the synthesis parameters and the powder's bulk density. Composite particles were compacted using spark plasma sintering (SPS). The compacted samples density was about 99-99.6% of the theoretical. Alumina was found on the grain boundaries of tungsten carbide.

Keywords: Cemented carbides, WC-8Co, Atomic layer deposition, Aluminum oxide, Grain growth inhibitor, Spark plasma sintering