DENSIFICATION AND HARDNESS OF AL2O3-CR2O3 SYSTEM WITH AND WITHOUT TI ADDITION

被引：24
作者：
CHO, SA
ARENAS, FJ
OCHOA, J
机构：
[1] Laboratory of Special Materials and Ceramics, Venezuelan Institute of Scientific Research (IVIC), Caracas, 1020A
[2] Materials Department, Technical University (IUT) in Caracas, Caracas, 1040A
来源：
CERAMICS INTERNATIONAL | 1990年 / 16卷 / 05期
关键词：
D O I：
10.1016/0272-8842(90)90044-G
中图分类号：
TQ174 [陶瓷工业]; TB3 [工程材料学];
学科分类号：
0805 ; 080502 ;
摘要：
The sintered bodies of the Al2O3Cr2O3 system form a solid solution (Al1-yCry)2O3 obeying Vegard's Law. The end member oxide, however, mutually deteriorates sinterability of the counterpart oxide, differing in the extent of its deterioration effect across composition, giving a sinterability minimum of roughly between y = 0·5-1. The sinterability curves of with and without Ti addition appear to be approximately parallel but the 5 wt% Ti-doped bodies result in much greater densification and hardness across the whole composition range. The added Ti nearly eliminates intragranular fine pores while it forms intergranular second phases; Al2TiO5 in Al2O3-rich samples and rutile (R-TiO2) in Cr2O3-rich ones. A 95·0% theoretically dense alumina with a very high microhardness (20 888 MPa) is obtained by adding 5 wt% Ti by conventional sintering in air. These values are nearly equal to or higher than those attained through very elaborative and practically awkward sintering practice and hot-pressing. © 1990.
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页码：301 / 309
页数：9
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