Open AccessSPS sintering of nitride ceramics
Author(s) -
Piotr Wyżga,
Piotr Klimczyk,
Jolanta Cyboroń,
P. Figiel
Publication year - 2019
Publication title -
mechanik
Language(s) - English
Resource type - Journals
ISSN - 0025-6552
DOI - 10.17814/mechanik.2019.5-6.41
Subject(s) - materials science , sintering , spark plasma sintering , fracture toughness , silicon nitride , ceramic , vickers hardness test , composite material , nitride , metallurgy , silicon , microstructure , layer (electronics)
Due to the unique properties of ceramics materials based on nitride, it could be used in the broadly understood technique. However, obtaining silicon nitride materials requires it to use the advanced methods of manufacturing, mostly because this material is difficult to sinter. Dense ceramic sinters were obtained from the system Si3N4-Al2O3-Y2O3 by applied pulsed current – SPS/FAST method (spark plasma sintering/field assisted sintering technique). The sintering parameters of the initial mixture were optimized to obtain the highest possible sinter properties, such as: density, Young’s modulus, hardness and fracture toughness. In the presented work the influence of pressure and pulse current, used in the SPS/FAST method, on sinterability and on selected physical and mechanical properties of the obtained materials was analyzed. The purpose of introducing the Al2O3 and Y2O3 additions to the Si3N4 matrix was to activate the hard-to-sinter silicon nitride powder and consequently to achieve a high density of the sintered samples. The best properties were characterized by sinter obtained in 1700°C and under pressure 63 MPa; the holding time at sintering temperature was 15 min. The density of the obtained sample has reached 98% theoretical value, and the other parameters were: Young’s modulus – 298 GPa, Vickers hardness – 17,7 GPa, fracture toughness – 6 MPa∙m1/2.