钛酸铝质空心球隔热制品的制备

Preparation of insulating bubble aluminium titanate-based products

以钛酸铝-莫来石-镁铝尖晶石质空心球(直径分别为1、2、3 mm的大、中、小球)为主要原料,加入与空心球成分相同的填充细粉以及不同种类的结合剂,经可塑成型,再经高温烧成后制备了钛酸铝质空心球隔热制品,并研究了结合剂类型(分别为Al2(SO4)3、PVA以及PVA与Al2(SO4)3按1:1质量比组成的复合结合剂)、烧成温度(分别为1 400、1 450、1 500、1 550、1 600℃保温1 h)、填充细粉加入量(质量分数,分别为10%、15%、20%、25%)以及空心球粒度配比(大、中、小球的质量比分别为2:4:4、3:4:3和4:4:2)对隔热制品性能的影响。结果表明:在大、中、小球的质量比为3:4:3,加入填充细粉的质量分数为20%,以及加入5%(质量分数)的PVA+Al2(SO4)3复合结合剂的条件下,采用可塑成型,经1 500℃1 h处理后,可以得到热导率为0.126 W.m-1.K-1,体积密度为1.27 g.cm-3,常温耐压强度为6.43 MPa的钛酸铝质空心球隔热砖试样。

The insulating bubble specimens were prepared using aluminium titanate -mullite -magnesium aluminate spinel bubbles （1,2 and 3 mm in diameter for large, medium and small bubble, respectively） as main starting materials ,adding padding fines （with the same composition of bubble） and various binders,then plasticity moulding and firing at high temperature. Effects of binder types including Al2 （SO4）3, PVA and PVA ＋AI2（SO4）3[ m（PVA） ： m（AIE（SO4）3） =1：1] ,firing temperatures （1 400,1 450,1 500,1 550 and 1 600 ℃, respectively,soaking for 1 h） ,addition of padding fines （10 wt%, 15 wt% ,20 wt% and 25 wt%,respec- tively） and the grain size composition of different bubbles （mass ratio of large,medium and small bubbles were 2 ：4：4,3：4：3 and 4：4 ：2,respectively） on the properties of insulating materials were studied. The re- sults showed that the insulating bubble specimen with 0. 126 W · m-1· K-1 of coefficient of thermal con- ductivity, 1.27g · cm-3 of bulk density and 6.43 MPa of compressive strength could be obtained when the mass ratio of large,medium and small bubbles was 3：4：3,addition of padding fines was 20 wt%, binder was 5 wt% of PVA ＋Al2（SO4）3 ,fired at 1 500 ℃ for 1 h using plasticity molding method.