effect of sintering parameters on the densification of zrb2-sic based composite

In this study, zrb2-sic ultra-high temperature ceramic composite was sintered using spark plasma sintering (sps) process with wc/hfb2 modifiers at different sintering temperatures of 1850, 1900, 2000, and 2050˚c for 8 and 25 minutes. the densification behavior of the composite was also examined using punch displacement-time and temperature-time measurement graphs during sps. phase and microstructure evaluations were also done based on xrd, eds, and fesem methods. the effect of sps parameters on the densification of zrb2-sic-based composite was studied. in this case, there was no displacement until the pressure was applied due to the low sinterability of boride powders. a zrb2-sic-based composite with a relative density of 90% was obtained at 2050˚c under 30 mpa for a 25-minute soaking time. the densification curve of this sample showed a typical “s” shape. the best water absorption and apparent porosity values obtained as 1.3 and 6.7%, respectively. the minimum and maximum punch displacement of the samples was 2.2 and 3.6 mm, respectively. use of wc/hfb2 modifiers led to the formation of byproducts of wb and hfb.