Long-term oxidation behavior and mechanical strength degradation of a pressurelessly sintered ZrB2–MoSi2 ceramic

Effect of Si3N4 Addition on Oxidation Resistance of ZrB2-SiC Composites

“…Vaporization of B2O3 leaves behind porous ZrO2, which gets subsequently filled by SiO2, formed by oxidation of SiC. On the other hand, Si3N4 preferably first oxidizes according to reaction (4). The ZSS shows lower mass gain compared to other ZrB2-based composites during oxidation at both 1200 and 1300 °C due to the presence of Si3N4.…”

“…But structural applications of the monolithic ZrB 2 at high temperatures are limited due to its inferior oxidation resistance [2]. Existing literature indicates that reinforcement of ZrB 2 with SiC [2,3] or MoSi 2 [4] or Si 3 N 4 [3,5] can lead to improvement in its oxidation resistance and mechanical properties [2][3][4][5]. In general, improvement of oxidation resistance of ZrB 2 by the above reinforcements is due to the formation of borosilicate (B 2 O 3 -SiO 2 ) rich scale [2][3][4][5][6][7].…”

“…In an earlier work by the authors, the oxidation behaviors of ZrB 2 -20 vol % SiC and HfB 2 -20 vol % SiC composites were compared, and the results showed that HfB 2 -20 vol % SiC composite possesses superior oxidation resistance compared to that of the ZrB 2 -20 vol % SiC composite. Therefore, an attempt has been made to improve the oxidation resistance of ZrB 2 -20 vol % SiC composite by addition of Si 3 N 4 . It has been shown that the addition of 2.5 wt % Si 3 N 4 to ZrB 2 significantly aides in its densification [8].…”

Effect of SiC whiskers and graphene nanosheets on the mechanical properties of ZrB2-SiCw-Graphene ceramic composites

“…Generally, the densification of ZrB 2 powder requires a high temperature above 2000°C at high pressure [5]. To improve the sintering properties of ZrB 2 , many different kinds of sintering aids are employed to fabricate composites, such as carbon [6], MoSi 2 [7], SiC [8,9], et al Moreover, ZrB 2 will be oxidized to ZrO 2 and B 2 O 3 under oxidizing conditions over 800°C [10]. In the high temperature application environment, it is proved that silicide will be oxidized to form a glassy phase which improves the oxidation resistance of ZrB 2 based ceramic composites [11,12].…”

Oxidation Behavior of a SPS Sintered ZrB2-SiC-MoSi2Ceramic at 1500 °C

“…The oxidation behaviors of some ternary composite ceramics system, such as ZrB 2 -SiC-TaC [9], ZrB 2 -SiC-ZrSi 2 [10], ZrB 2 -SiC-TaSi 2 [11], ZrB 2 -SiC-LaB 6 [12], ZrB 2 -SiC-ZrO 2 [13] and so on, have been researched intensively. MoSi 2 was found to be an effective additive to improve the sinterability and oxidation resistance of ZrB 2 ceramic [14,15,16], the oxidation behavior of ZrB 2 -MoSi 2 ceramic has been studied [17,18]. However, the oxidation behavior of ZrB 2 -SiC-MoSi 2 ceramic at high temperature was rarely reported.…”