锆刚玉加入对刚玉-尖晶石浇注料性能的影响

Effect of fused zirconia corundum on properties of corundum-spinel castables

在刚玉-尖晶石浇注料的配比组成中分别加入ZrO2质量分数为28.46%和38.47%的两种电熔锆刚玉颗粒,研究了电熔锆刚玉颗粒的粒度(5～3、3～1和1～0.5 mm)、加入量(质量分数分别为3%、5%和8%)对刚玉-尖晶石浇注料的加热永久线变化率、烧后常温抗折强度、高温抗折强度及热震后弹性模量的影响,并观察了试样的显微结构。结果表明:1)试样的加热永久线变化率随锆刚玉粒度的增大而增大,随锆刚玉加入量的增多而增大,引入锆刚玉Z40的试样的加热永久线变化率基本上比引入锆刚玉Z25的大;2)烧后试样的常温抗折强度、高温抗折强度和弹性模量均以空白试样的为最大,均随锆刚玉粒度的减小而增大,随锆刚玉加入量的增多而减小;3)在刚玉尖晶石浇注料中适当加入锆刚玉而产生微裂纹,尽管降低了材料的强度和弹性模量,但对提高抗热震性有一定的积极作用。

Two kinds of fused zirconia corundum particles with ZrO2 contents of 28.46% and 38.47% were added into corundum-spinel castables to study the effects of grain size（5-3,3-1 and 1-0.5 mm） and addition（3%,5%,and 8%） on the permanent linear change,cold/hot modulus of rupture,and elastic modulus after thermal shock of the castables.The microstructure was observed as well.The results show that：（1）permanent linear change increases with the increase of the fused zirconia corundum grain size or the increase of fused zirconia corundum addition;the permanent linear change of specimen with zirconia corundum Z40 is basically higher than that of specimen with zirconia corundum Z25;（2）the blank specimen has the highest cold modulus of rupture,hot modulus of rupture,and elastic modulus;these properties increase as fused zirconia corundum grain size decreases and decrease as addition of the fused zirconia corundum increases;（3）micro cracks form due to the introduction of the fused zirconia corundum,and these cracks decrease the strength and elastic modulus of the material but improve the thermal shock resistance.