Sintering of Al-Zr based oxide ceramics using thermal plasma

A novel and low cost extended are thermal plasma heating (EATPH) reactor [R oul et al., JMSP 6 (1) (1998)] has been used to sinter Al-Zr oxide ceramics within a few minutes in Ar atmosphere instead of a few tens of hours by co nventional furnace heating. Critical experimental parameters such as plasma power (kW), plasmogen gas flow rate, sintering time and electrode spacing distance are optimized to achieve high density sintered materials. It is no ted that sintering time is approximately reciprocal to plasma power. Higher plasma power with less sintering time can generate high-density homogeneou s material without significant grain growth. XRD and SEM studies were carri ed out to characterize and evaluate the sintered materials. Surface morphol ogy revealed uniform particle size distribution in long-range order, with n o runway grain growth during this EATPH sintering process. This simple EATP H method provides an alternative and quick technique for tailoring high tem perature ceramic materials over conventional sintering method due to fast h eat and mass transfer kinetics inside thermal plasma reactor. (C) 2001 Else vier Science B.V. All rights reserved.