主晶相方镁石熔点为2800℃，在真空中1600℃就开始升华，在还原气氛中2000℃以上开始升华，密度大于3.40g/cm，气孔率0%～10%，莫氏硬度5.5，抗碱性炉渣侵蚀性很强。97电熔镁砂，方镁石常呈立方体、八面体或不规则粒状，立方体解理完全;线膨胀系数α=(14～15)×10/℃(0～1500℃)，并随温度升高而增大。
热导率λ=123.5W/(m·K) (100℃时)，随温度上升而下降。弹性模量为1.96MPa。化学性质稳定，在1500℃的高温下与除硅砖以外的各种耐火材料之间不起反应或弱反应。方镁石的晶粒尺寸随煅烧温度的提高和保温时间的延长而增大，相应的抗渣性也得到改善。中国对电熔镁砂的质量要求见表。
生产工艺
电熔镁砂的生产工艺流程短而简单，但设备投入和资源消耗大。我国电熔镁砂产业多采用电弧炉熔融天然菱镁矿石制备电熔镁砂，生产工艺技术装备落后，功率低、容量小、效率低、自动化程度低，生产出的电熔镁砂产品品位不高，导致镁资源利用率低，环境污染严重。
The melting point of the main crystalline phase magnesia is 2800℃, which begins to sublimate at 160℃ in a vacuum and above 2000℃ in a reducing atmosphere, with a density greater than 3.40g/cm, porosity of % to 10%, Mohs hardness of 5.5, and strong resistance to alkaline slag erosion. 97 electric fused magnesia sand,nesia is often cubic, octahedral, or irregular granular, with complete cubic cleavage; the linear expansion coefficient α=(14～15)×1/℃(0～1500℃), and increases with increasing temperature.
The thermal conductivity λ=123.5W/(m·K (at 100℃), which decreases with increasing temperature. The modulus of elasticity is 1.96 MPa. Chemically stable, it does not or react weakly with various refractories at high temperatures of 1500℃ except for silica brick. The grain size of magnesia increases with the increase of sintering temperature and holding time, and the corresponding slag resistance is also improved. The quality requirements for electric fused magnesia sand in China are shown in the table.
97 electric fused magnesia sand
Production process
The production process flow of electric fused magnesia sand is short and simple, but it requires large equipment and resource consumption. China's electric magnesia sand industry mostly uses electric arc furnace to melt natural magnesite ore to prepare electric fused magnesia sand, the production technology equipment is backward, low power, small capacity, low efficiency, low degree of automation, and the electric fused magnesia sand product grade is not high, resulting in low rate of magnesite resources and serious environmental pollution.
