Paper Title:
Laser Zone-Remelted Alumina-Based Eutectic In Situ Composite
  Abstract

Due to excellent oxidation and corrosion resistance at elevated temperature, oxide ceramic could be the preference served at high temperature oxidizing atmosphere over a long period of time. In recent years, alumina-based eutectic in situ composite prepared by various solidification techniques, which has superior properties even close to the melting point about 2100K, has been paid much attention. In this paper, Al2O3/YAG/ZrO2 ternary eutectic and hypoeutectic ceramics are prepared from melt by laser zone-remelting technique, the rapid solidification characteristic and the mechanical property of the composites are investigated. The results show that: (1) Compared to sintered composite with the same composition, laser zone-remelted Al2O3/YAG/ZrO2 eutectic in situ composite has different microstructure showing fine interpenetrated network with Al2O3, YAG and ZrO2 phases continuously intergrown, while none of pores, grain boundaries and amorphous phases is found. (2) The scanning rate and the power density of the laser beam has strong effect on the microstructure morphology. When the power density is determined, the eutectic spacing is reduced with the scanning rate increased. The characteristic eutectic spacings and phase sizes of YAG and Al2O3 are about 2~3μm, and the characteristic dimension of ZrO2 is less than 1μm. (3) The hardness and the room-temperature fracture toughness of Al2O3/YAG/ZrO2 eutectic are respectively Hv=16.7±2.0 GPa and KIC=8.0±2.0 MPa.m1/2, and those of hypoeutectic are respectively Hv=15.8±2.0 GPa and KIC=3.9±1.0 MPa.m1/2.

  Info
Periodical
Materials Science Forum (Volumes 539-543)
Main Theme
Edited by
T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran
Pages
832-836
DOI
10.4028/www.scientific.net/MSF.539-543.832
Citation
J. Zhang, H. J. Su, L. Liu, H. Z. Fu, "Laser Zone-Remelted Alumina-Based Eutectic In Situ Composite", Materials Science Forum, Vols. 539-543, pp. 832-836, 2007
Online since
March 2007
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Rong Tu, Wenjun Li, Takashi Goto
Abstract:The TiC-TiB2-SiC system was a ternary eutectic, whose eutectic composition was 34TiC-22TiB2-44SiC (mol%). A TiC-TiB2-SiC ternary eutectic...
1057
Authors: D.K. Wang, H.C. Wu, R.K. Shiue, C. Chen
Abstract:Vacuum repair brazing of Inconel 939 using various ratios of DF3 and Rene 80 powder mixtures has been performed in this study. The porosity...
71
  | Authors: S. Mohsen Sadrossadat, Sten Johansson
Abstract:Improved mechanical and physical properties of an Al-Si alloy as a well-known casting alloy is strongly dependent upon the morphology of...
505
Authors: Dan Huang, Yan Li Wang, Ying Wang, Hong Bao Cui, Xue Feng Guo
Abstract:The thermodynamic analysis in Mg-SiO2 system was conducted for the determination of the priority reaction at experimental temperature. Then,...
1775
Authors: Zhi Qiang Jiang, Xi Lan Feng, Xian Zhang Feng
Abstract:The microstructures of B-bearing cast steel containing 0.8-1.2 wt.%B, 0.8-1.2 wt.%Cr, 1.0-1.5 wt.%Mn, 0.6-1.0 wt.%Si and 0.10-0.25 wt.%C have...
878