材料期刊网

目前由于国内对淀粉作为造孔剂制备多孔材料的研究并不全面，且研究的淀粉种类比较单一，因此以高岭土、硅灰石、蓝晶石、Al（OH）3为原料，分别以不同种类的淀粉为造孔剂和结合剂原位固化制备了钙长石－莫来石轻质耐火材料，研究了马铃薯、玉米、小麦、木薯、番薯等五种淀粉对浆料的黏度、原位固化后的坯体强度及烧成制度的影响，并分析了烧后试样的显微结构、气孔形状、线收缩率及耐压强度。结果表明：在淀粉糊化膨胀后，由于玉米淀粉黏度大，小麦淀粉大部分能形成球状并将粉料压紧，加大了颗粒之间粘结程度，因此，加入这两种淀粉的浆料干燥后坯体强度大，分别为5．37和5．26 MPa。煅烧后，加入小麦淀粉的试样形成的气孔大部分为球状且体积较小，其耐压强度最大，为9．12 MPa。加入的淀粉颗粒粒径越大（d0．5由大到小依次为：马铃薯＞玉米＞小麦＞木薯＞番薯），糊化膨胀后体积越大，试样煅烧后形成的孔径越大，其显气孔率越大，体积密度越小。

The anorthite-mullite lightweight refractories were prepared by starch in-situ consolidation,using kaolin,wollastonite,kyanite,Al(OH)3 as starting materials,different kinds of starches (potato,corn,wheat, cassava,and sweet potato)as pore forming agent and binder.Effects of various starches on viscosity of the slurry,strength of green body,and firing schedule were researched,and the microstructure,pore shape,linear shrinkage and strength of specimens after fired were studied.The results show that,after the gelatinization swelling of starch,because the slurry with corn starch has higher viscosity,and most of the wheat starch in the slurry can form spherical particles,which helps to press the powder materials and en-hance the bonding degree of particles,so the green bodies with corn starch or wheat starch after drying have great strength (5.37 MPa,5.26 MPa,respectively).After firing,the specimens with wheat starch have most spherical and small pores,and the maximum crushing strength (9.12 MPa).The larger the size (d0.5 )of the starch (potato >corn >wheat >cassava >sweet potato),the larger the volume after gelatini-zation swelling,the larger the pore size of specimens after firing,the bigger the apparent porosity,the smal-ler the bulk density.