高强度堇青石-莫来石棚板的研制

Development of high strength cordierite-mullite deck

以堇青石（1～0．5、0．5～0．2、〈0．088mm）和莫来石熟料（M60，1～0．5mm）为主要原料，加入25％（w）的由轻烧MgO粉、α-Al2O3微粉及添加剂（紫木节和KOH）组成的混合粉，按堇青石与莫来石的质量比分别为40：35、42．5：32．5和45：30配料、混练、成型后，分别在1300、1350和1400℃均保温3h条件下烧成，合成出堇青石-莫来石质棚板试样，并检测试样的常温及高温物理性能，同时进行XRD、SEM及EDS分析。结果表明：按m（堇青石）：m（莫来石）=45：30配料，在1350℃ 3h合成的棚板材料的各项性能指标最好，其主要晶相为堇青石和莫来石，且显微结匀均匀，晶间生成大量的原位堇青石和莫来石晶粒，骨料之间的“联接桥”发育良好，材料具有较高的抗折强度。

Cordierite -mullite deck specimens were prepared using cordierite （1 -0.5,0.5 -0.2 and ≤0. 088 mm） and mullite （M60,1 -0. 5 mm） chamotte as main starting materials, adding 25% mixture of light-burned MgO powder,α-Al2O3 micropowder and additives （knar clay and KOH）, batching according to 40：3.5, 42..5 ： 32.5 and 4.5 ： 30 of mass ratio of cordierite to mullite, mixing, shaping, and fired at 1300, 1 350 and 1 400 ℃ for 3 h, respectively. Physical properties of the specimens both at room temperature and elevated temperature were tested and the specimens were analyzed by XRD, SEM and EDS. The results showed that when the mass ratio of cordierite to mullite is 4.5：30, the deck fired at 1 350℃ for 3 h had the best properties, in which the main crystal phases were cordierite and mullite,the microstructure was uniform, a large quantity of in-situ cordierite and mullite crystal grains formed in intercrystalline,the connecting bridge among aggregates developed well ,which improved the modulus of rupture of the materials.