Production of AlN-Si-Al Ceramic-Metal Composites via Pressurless Infiltration Method

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In this work, the production of light (∼2,9 g/cm3) and dense ( 99 %) AlN based ceramic metal composites was conducted by the pressureless melt infiltration method. These composites contain a high ceramic volume fraction ( 50 vol %) which is the result of the reaction between Si3N4 and Al in the Si3N4-Al system. The production of the ceramic-metal composites was achieved via infiltrating 2024 Al alloys at different temperatures and holding times into the porous pellets which were prepared using α-Si3N4 powder. These experiments were conduced in two ways: (i) Infiltration at a constant holding time (1 h) in the temperature range of 900-1400°C at intervals of 100°C. (ii) Infiltration at a constant infiltration temperature (1200°C) with a holding time in the range of 1-5 h at intervals of 1 h. Qualitative phase analysis of the produced composites confirmed the exisitence of the AlN, Si, Al and CuAl2 phases in the microstructure and revealed that the Si3N4 phase was completely consumed as a result of its reaction with the Al phase. The SEM analyses indicate that these materials are quite dense and fine-grained ( 0,5 μm).

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Pressureless infiltration , ceramic , metal composite , AlN , Si3N4

Afyon Kocatepe University Journal Of Science an‎d Engineering

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Afyon Kocatepe University Journal Of Science an‎d Engineering