加热体积膨胀剂对壁流式蜂窝陶瓷堵孔材料膨胀性能的影响

研究了壁流式蜂窝陶瓷堵孔材料的制备工艺,探讨了加热体积膨胀剂的加入量、烧成温度以及各烧成温度下堵孔材料的膨胀与收缩情况对壁流式蜂窝陶瓷堵孔材料膨胀性能的影响。研究结果表明,当配方中加入25 wt%的加热体积膨胀剂,在1160℃下烧成,可以制备出与壁流式蜂窝陶瓷载体结合牢固,抗折强度为3.72 MPa且干燥收缩率和烧成收缩率符合壁流式蜂窝陶瓷性能要求的堵孔材料。

磷酸反应槽内衬碳砖膨胀试验

碳砖的膨胀系数是碳砖选择和结构设计时要考虑的关键参数。本文通过碳砖水中膨胀和水中加热膨胀的两种试验,初步模拟了内衬碳砖的两种服役工况(水试和操作)。结果表明,水中膨胀和水中加热膨胀系数远大于其常规空气中的膨胀系数;不同类型碳砖膨胀系数差别较在常规空气介质中更显著;对树脂热固性碳砖,其水中和水中加热的膨胀系数在不同方向上差别较大,采用树脂热固性碳砖时,排砖方式、膨胀缝的设置等应更加谨慎考虑。

卷制异型衬套压装工艺及装备

研究开发了卷制异型衬套压装工艺及装备。采用连杆小头孔加热膨胀的方法减小过盈量;采用内外导向定位夹具,保证衬套压装过程中不发生歪斜、拉边和损坏衬套钢背等现象,确保衬套与连杆小头孔的贴合度指标达标。

Effects of Magnesia Fines Addition and Spinel with Different Compositions on Thermal Expansion Behavior of Alumina Magnesia Castables

Effects of magnesia fines addition （ 4%, 6% and 8% in mass ） and spinel with different compositions （alumina-rich, magnesia-rich and stoichiometric spi-nel） on thermal expansion behavior of alumina magne-sia castables were researched using tabular corundum, magnesia fines, spinel fines, p-A12O3, Secar-71 cement and SiO2 fume as main starting materials. The results show that： （1） thermal expansion coefficients of speci- mens with 4 mass% and 6 mass% magnesia fines have the similar change tendency, increasing slightly with temperature rising ; when magnesia addition is 8 mass% , the thermal expansion coefficient increases ob-viously at Ⅰ 050 ℃ and reaches the peak at 1 350 ℃ ; （2） when MgO content is the same, the specimen with magnesia-rich spinel has the lowest thermal expansion coefficient; （3） for the castables specimens with the same MgO content, the specimen with magnesia has higher thermal expansion coefficient than that with pre-synthesized spin, el, which is related with the secondary spinelization dttriag the heating process.