EffectsandOxidation Kinetics of Holding Time on the Beta-Sialon Bonded MgAl$lt;inf$gt;2$lt;/inf$gt;O$lt;inf$gt;4$lt;/inf$gt;-C Composites

A β-Sialon bonded MgAl 2 O 4 -C refractory was prepared in-situ by fused spinel, silicon powder, flake graphite as raw materials, and calcium lignosulfonate with the concentration of 1.25 g/mL as the binder.The samples were sintered under N 2 atmosphere at 1450 for 1, 2 3 ℃ and 4 h, respectively.The effects of holding time on the conven-无 机 材 料 学 报 第 32 卷 stages: chemical reaction rate controlling stage, diffusion rate controlling stage, and co-effect controlling of chemical reaction and diffusion rate stage.