材料期刊网

我们研究中温系窑用锥(пК123—146)产生冻结现象的条件、原因及不冻结锥应有的化学矿物组成,指出该系锥的冻结是由于锥体中的液相在适当的条件下析出晶体所致。等轴晶系方石英的析晶引起ПК123—130号锥发生冻结;而ПК132—146各号锥冻结的原因则可能是由于析出莫来石。Na_2O,K_2O含量对冻结有决定性的影响。ПК130—123各号锥应用钾长石,НК132—146各号锥应用钢长石可以制得不会冻结的该系窑用锥。还有在研究MgO对冻结的作用时证明以菱苦土作为MgO的原料对解决窑用锥的冻结问题是有害而无益的。

The phenomenon that a pyrometric cone does not bend over at its own soften-ing temperature is called "freezing". Such phenomenon has been studied for thecones of middle temperature range (SK7-16, or ПК123-146). It is shown that the freezing of a pyrometric cone is due to the formationof certain refractory crystals from molten phases in the cone when the furnacetemperature is either unsteady or kept for a rather long period just balow its sof-tening point. In the cones SK7-10, the refractory crystals formed are of chry-santhemum shape and found petrographically to be isometric cristobalite In thecones SK11-16, apart from crystals found in SK7-10, many needle-like crystalsare formed, X-ray examination shows that they are possibly mullite. If the sodium oxide content is high relative to total alkali in cone materialSK7-10, or potassium oxide is high in SK11-16, may cause the cones to freeze.Thus in order to prepare a series of non-freezing cones the potash felspar shouldbe used as raw material for SK7-10, and soda felspar for SK11-16. It wasattempted to reduce their freezing tendency by substitution CaO by MgO intro-duced as magnesite, but the result was very unsatisfactory.