The magnesia-chrome specimens were prepared using magnesite clinker, chromite and chromium powder as raw materials, carboxymethylcellulose sodium as binder, after pressing, firing at 1 600 ℃ for 3 h to determine the effect of chromium powder on the physical and chemical properties of magnesia-chrome refrac-tory. The effect of chromium powder (mass percent were 0%, 0.3%, 0.5%, 1%, 1.5%respectively) on physical and chemical properties of magnesia-chrome refractory were researched, including, porosity rate, flexural strength, compressive strength and thermal shock resistance. The results show that the porosity of samples is obviously reduced and its strength is improved with the addition of 0.3 % chromium powder. However, the properties would be worsened if the addition of chromium powder were too excessive. The strength of the spec-imen added 1.5%chromium powder is obviously decreased with increased porosity. Moreover, the size of pores become larger, owing to the serious expansion of the oxidation reaction of chromium powder. To improve the properties of magnesia-chrome refractory, the addition of chromium powder should be around 0.3%.%为了研究金属铬粉对镁铬耐火材料各理化性能的影响，以镁砂、铬铁矿、金属铬粉为原料，羧甲基纤维素钠为结合剂，经压制并在1600℃下保温3 h烧制成镁铬耐火试样，系统研究金属铬粉的添加量（加入量分别为0%、0.3%、0.5%、1%、1.5%）对镁铬耐火材料气孔率、抗折强度、耐压强度和抗热震性的影响.结果表明，添加0.3%的金属铬粉可明显降低试样的气孔率，使试样致密烧结，强度也显著提高，但对抗热震性影响不明显；随着金属铬粉添加量的增多，各理化性能逐渐恶化，添加1.5%金属铬粉的试样强度明显降低，气孔率升高且气孔孔径明显变大，这是因为金属铬粉发生氧化反应产生严重的膨胀.为了提高镁铬耐火材料的理化性能，金属铬粉的添加量应在0.3%左右.
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