(1) the volume of magnesium cement under natural curing is a continuous expansion process, the linear expansion rate is 0.1~0.2%, and the volume expansion rate is about 1%.

②菱镁矿在服烧过程中不可避免地产生局部过烧，使一部分MgO呈死烧状态，过烧的MgO水化过程很慢，当已形成强度的水泥石中的MgO再遇水进行水化时，生成Mg(OH)2，体积膨胀120%;

In the process of burning the magnesite inevitably produces local overheating, which makes a part of MgO in a state of death, and the MgO hydration process of over burning is very slow. When the MgO in the cement stone has been formed, the Mg (OH) 2 is generated and the volume expansion is 120%.

③轻烧氧化镁中游离CaO水化时体积膨胀90%，而卤片中存在着 SO42-，当Ca(OH)2转化成石膏时，固体体积将增加2倍以上，导致制品变形，这也是限制轻烧氧化镁中游离CaO含量、卤片中SO42-含量的原因;

(3) the volume expansion of free CaO in light burning Magnesium Oxide is 90%, while SO42- exists in the halogen slices. When Ca (OH) 2 is converted into gypsum, the volume of solid will increase more than 2 times, resulting in the deformation of the products. This is the original cause of limiting the free CaO content in Magnesium Oxide and the content of SO42- in the halogen slices.

④MgO-Mg-C12-H2O系统水化过程是一个强烈的放热反应过程，而生产的99无码熟妇丰满人妻啪啪体积又大，若环境温度较高，则反应升温过程，板材本体温度过高，反应不充分，造成较大的结晶应力和热膨胀应力，使制品体积膨胀。

(4) the hydration process of MgO-Mg-C12-H2O system is a strong exothermic reaction process, and the volume of the pipeline is large. If the temperature of the environment is high, the reaction temperature process is high, the temperature of the plate is too high and the reaction is insufficient, resulting in the larger crystallization stress and thermal expansion stress, so that the volume of the product is expanded.