Microstructures and mechanical properties of liquid-phase sintered seeded silicon carbide

Densification of SiC by SPS-effects of time, temperature and pressure

“…Indeed, mechanical properties are lowered. [1][2][3][4] To reach full density with pure SiC, it was decided to use a relatively new process that is, field activated sintering, also known as spark plasma sintering (SPS). The SPS process allows various types of powders to be sintered.…”

Hardness degradation in liquid-phase-sintered SiC with prolonged sintering

“…In this context, the most widely studied additive system for SiC is Y 2 O 3 -Al 2 O 3 , especially when these components are chosen in the form Y 3 Al 5 O 12 . Typically, prolonged sintering in an Ar atmosphere is used to process such a liquid-phase-sintered (LPS) SiC to improve its long-crack toughness, [8][9][10][11][12][13] since the sintering duration promotes grain coarsening, and the crack-bridging toughening mechanism in LPS SiC is more efficient with increasing grain size. 14 However, it has been shown that LPS SiC resulting from prolonged sintering, the so-called "in situ toughened SiC", are much softer than those sintered for shorter times.…”

“…14 However, it has been shown that LPS SiC resulting from prolonged sintering, the so-called "in situ toughened SiC", are much softer than those sintered for shorter times. 8,10,13,15 Whereas reduced hardness facilitates machining of LPS SiC parts, it can limit their utility in various structural applications. Although hardness degradation with prolonged sintering is a well-documented effect, to the best of the authors' knowledge no studies have explored the underlying causes of the phenomenon.…”

Effect of liquid-phase content on the contact-mechanical properties of liquid-phase-sintered α-SiC

“…[1][2][3][4][5][6][7][8][9][10][11][12] The mechanical properties of LPS SiC ceramics, at both ambient and elevated temperatures, have been studied extensively. [5][6][7][8][9][10][11][12] However, most of the studies on the mechanical properties of LPS SiC lack a common experimental platform, which precludes the extraction of guidelines for the design of materials with tailored mechanical properties. Therefore, systematic studies aimed at elucidating the roles of the various processing variables on the mechanical properties of LPS SiC are still required.…”

“…8,9,[13][14][15] In this study we focus on investigating the effect of intergranular phase (YAG) content on the room-temperature contact-mechanical properties of pressureless, LPS ␣-SiC ceramics. Here we show that YAG vol.% has a profound effect on the hardness, toughness, and slidingwear resistance of LPS SiC.…”