In:
Materials Science Forum, Trans Tech Publications, Ltd., Vol. 745-746 ( 2013-2), p. 610-615
Abstract:
The microstructure of Al 2 O 3 -Cr 2 O 3 refractories is an important factor to affect its high temperature performance. The Al 2 O 3 -Cr 2 O 3 green bodies were prepared by hot pressing using aluminum oxide and Cr 2 O 3 powder mixture by adding a binder. And then the specimens were sintered at 1650 for 4h in the electric muffle furnace. Properties of specimens with different species of Al 2 O 3 powders were studied, including α-Al 2 O 3 powder, ρ-Al 2 O 3 powder, and fused corundum powder. Moreover, three sizes of α-Al 2 O 3 powder (D 50 =0.8 μm, 1.4 μm, 4.0 μm) were used as additive. Properties of specimens, including apparent porosity, bulk density, cold modulus of rupture, pore size distribution were tested. The morphology of sintered specimens was analyzed by the Scanning Electron Microscope. The results showed that the specimens adding α-Al 2 O 3 powder had the better properties since α-Al 2 O 3 powder has higher sintering activity, and it was more efficient for Al 2 O 3 -Cr 2 O 3 solid solution. The specimens with α-Al 2 O 3 had lower porosity, higher bulk density and cold modulus of rupture, and more uniform pore distribution. There were great differences in sintering activity for specimens with different particle size of α-Al 2 O 3 powder. And the microstructure of Al 2 O 3 -Cr 2 O 3 was significantly dissimilar. The specimen with the addition of the activated alumina powder of D 50 with the size of 1.4 μm and bimodal size distribution showed the perfect performance, including high density and high flexural strength. The experimental results showed that the microstructure of this specimen was uniform and its pore size was homogeneous. This special microstructure is beneficial for improving the slag resistance and thermal shock resistance of Al 2 O 3 -Cr 2 O 3 refractories.
Type of Medium:
Online Resource
ISSN:
1662-9752
DOI:
10.4028/www.scientific.net/MSF.745-746
DOI:
10.4028/www.scientific.net/MSF.745-746.610
Language:
Unknown
Publisher:
Trans Tech Publications, Ltd.
Publication Date:
2013
detail.hit.zdb_id:
2047372-2
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