为提高钙长石材料的高温性能，需引入莫来石相，因此，以煤矸石、氢氧化铝和轻质碳酸钙为原料，PVA溶液为结合剂，以莫来石理论生成量（w）分别为20％、40％、50％、60％和80％来改变原料配比，制备了具有不同莫来石含量的多孔钙长石－莫来石陶瓷，并研究了原料配比对其物相组成、显微结构和性能的影响。结果发现：1）随着氢氧化铝加入量增加，试样的显气孔率变化不大，但孔径尺寸不断减小；2）各试样的相组成为钙长石、莫来石和少量刚玉，随着氢氧化铝加入量的增加，莫来石含量增加，钙长石含量减小；3）原料配比对二次莫来石化影响很大，影响着氢氧化铝假象间结合颈部中莫来石、钙长石和玻璃相的含量，进而影响试样的常温强度、高温强度；4）得到了显气孔率为44％～50％，常温抗折强度在5．2～10．9 MPa，高温抗折强度在4．3～6．5 MPa，具有不同莫来石含量的多孔钙长石－莫来石陶瓷。%To enhance the hot properties of anorthite material,porous anorthite-mullite ceramics were pre-pared using gangue,Al(OH)3 and light weight CaCO3 as starting materials,and PVA solution as binder. The starting material proportions are based on the theoretical mullite formation ratios of 20%,40%,50%, 60% and 80% by mass,respectively.The effect of the starting material proportion on the microstructure and phase composition of specimens was investigated.The results show that:(1)with the increase of Al(OH)3 addition,the apparent porosity changes a little,but the pore size decreases;(2)the phases of the speci-mens are anorthite,mullite and minor corundum;with the increase of Al(OH)3 addition,the mullite content increases and the anorthite content decreases;(3)the starting material proportion affects strongly the sec-ondary mullitization,and then affects the contents of mullite,anorthite and glass phase in neck bonds be-tween Al(OH)3 pseudomorphs,which determines the strengths at room and high temperatures;(4)porous anorthite-mullite ceramics with different mullite contents were obtained,with apparent porosity of 44% -50%,modulus of rupture of 5.2 -10.9 MPa at room temperature and 4.3 -6.5 MPa at high temperatures.
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