摘要
以电熔刚玉和SiC为基料的制品中添加适量亚微米级的绿铬 (α Cr2 O3)时 ,烧成过程中α Cr2 O3生长到 1～ 5μm ,并与刚玉表面接触区发生互扩散行为。SiC在氧化层中氧化并形成玻璃纤维 ,使氧化层的组分变为Al2 O3-Cr2 O3-SiO2 系。所形成的高硅质液相能促进 (Al2 -x,Crx)O3固溶体析晶 ,晶体呈较大的六方柱状自形晶 ,长度达 5～ 2 0 μm ,长径比 ( )为 5～ 1 0。但此液相中不含Cr2 O3。
A sintered product based on fused corundum and SiC is manufactured by adding eskolaite in submicrometer grain size.In sintering process,the eskolaite grows into 1～5 μm and interdiffusion takes place on local contact surfaces of eskolaite and fused corundum.In the oxide layer,SiC is oxided into SiO 2 and forms glass fiber.The composition of oxide layer transforms into system of Al 2O 3-Cr 2O 3-SiO 2.Liquid-phase formed by SiO 2 with high siliceous promotes crystallization of ( Al 2-x,Cr x)O 3 solid solution in euhedal of hexahedral column in size of 5～20 μm with =5～10.No Cr 2O 3 exists in glass phase.
出处
《耐火材料》
CAS
北大核心
2004年第5期353-356,共4页
Refractories
