Abstract: To optimize the properties of self-bonded SiC refractories,the specimens were fabricated using silicon carbide (3-1,≤1,and ≤0.074 mm),silicon powder (≤45 μm) and graphite (≤10 μm) as raw materials,and Cr₂AlC powder (≤74 μm) as an additive,pressing under 150 MPa into 25 mm×25 mm×40 mm shapes,drying at 110 ℃ and heat treating at 1 300 ℃.The effects of the Cr₂AlC addition (0,1%,3%,and 5%,by mass) on the cold physical properties,sodium sulfate corrosion resistance,and steam oxidation resistance of the materials were investigated.The results reveal that with the increasing Cr₂AlC addition,the cold physical properties of the specimens after drying at 110 ℃ differ slightly;however,the cold physical properties of the specimens fired at 1 300 ℃ show a gradually increasing trend;while the sodium sulfate corrosion resistance initially increases and then decreases.When the Cr₂AlC powder addition is 3%,the specimen exhibits a low mass change rate in the steam,demonstrating good overall performance.

Key words: Cr₂AlC powder, self-bonded SiC refractories, cold physical property, sodium sulfate corrosion resistance

摘要： 为优化自结合SiC耐火材料的性能,以碳化硅(3~1、≤1和≤0.074 mm)、硅粉(≤45 μm)和石墨(≤10 μm)为原料,Cr₂AlC粉体(≤74 μm)为添加剂,在150 MPa下压制为25 mm×25 mm×40 mm的坯体,经110 ℃干燥、1 300 ℃热处理后制备自结合SiC耐火材料。研究了Cr₂AlC加入量(加入质量分数分别为0、1%、3%和5%)对其常温物理性能、抗硫酸钠侵蚀性能以及抗水蒸气氧化性能的影响。结果表明:随着Cr₂AlC加入量增加,经110 ℃干燥后试样的常温物理性能差异不大,经1 300 ℃热处理后试样的常温物理性能呈现出逐渐升高的趋势,抗硫酸钠侵蚀性能先升高后降低。当Cr₂AlC粉体加入量为3%(w)时,试样在水蒸气中的质量变化率也较低,综合性能较优。

关键词: Cr₂AlC粉体, 自结合SiC耐火材料, 常温物理性能, 抗硫酸钠侵蚀性能