为了研究不同尖晶石组成和含量对RH浸渍管用方镁石－尖晶石质耐火材料性能的影响，以高纯烧结镁砂、电熔镁砂、三种预合成烧结镁铝尖晶石（Al2 O3的质量分数分别为50％、66％和78％）为原料制备了方镁石－尖晶石耐火材料试样。研究表明：1）加入尖晶石会降低试样的力学性能和热膨胀系数，但可显著提高试样的抗热震性；2）由于原位生成尖晶石的影响，当加入富铝尖晶石时试样的力学性能和热膨胀系数下降，抗热震性提高；3）加入的尖晶石种类和含量不同，试样的断裂机制有所不同，随着尖晶石加入量的增加以及由富镁尖晶石转变为富铝尖晶石，试样由穿晶断裂转变为沿晶断裂。综合考虑，选择富镁尖晶石且尖晶石加入量（w）为16％～18％时，试样的综合性能较优。%In order to study the effect of spinel content and composition on properties of periclase-spinel re-fractories used in RH snorkels,high purity sintered magnesia,fused magnesia and three kinds of pre-syn-thesized magnesium aluminate spinel (alumina content of 50%,66%,and 78% by mass,respectively) were used as starting materials to prepare periclase-spinel specimens.Results reveal that:(1)adding spi-nel reduces strengths and CTEs,while increases resistance to thermal shock significantly;(2)due to the formation of in-situ spinel while sintering,adding alumina-rich spinel leads to decreases in strengths and CTEs but improvement in thermal shock resistance;(3)the fracture mechanism differs from transgranular fracture to intergranular fracture as spinel addition rising and the change from magnesia-rich spinel to the alumina-rich spinel.In conclusion,a better comprehensive properties can be reached with 16%-18% ad-dition of magnesia-rich spinel.
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