Low carbon AI2O3-C slide plate materials were prepared using tabular corundum,α-AI2O3 mi-cropowder,graphite,Al powder and Si powder as main starting materials,and phenolic resin as binder. The additions of tabular corundum,α-AI2O3 micropowder and graphite were fixed at 85% (mass percent,similar hereinafter) ,5% and 2% , respectively. The total amount of Al powder and Si powder was 8% , and the mass ratios of Al powder to Si powder were 0:8,5:3,3=5 and 8: 0, respectively. Hot modulus of rupture, stress-strain relationship and thermal shock resistance of these materials were investigated after graphite-embedded firing at 1 500 ℃ for 3 h. Phase compositions and microstructure were analyzed. The results show that these materials possess improved high temperature strength and good thermal shock resistance. When m(AI)/m(Si) varies from 0:8 to 8 :0,HMOR at 1 400 ℃ increases significantly from 10.4 MPa to 32.4 MPa;the maximum strain under 6.5 MPa stress at 1 400 ℃ decreases from 215 μm to 90μm;residual strength ratio after 3 thermal shocks(1 100 ℃,air quenching) decreases from 80% to 65%. This is attributed to the formation of nonoxides AI4C3-AIN and SiC because Al and Si react with C,CO and N2. These nonoxldes fill in the corundum skeleton, strengthening and toughening it, and enhance high temperature mechanical properties of low carbon AI2O3-C slide plate materials.%以板状刚玉、α-Al2O3微粉、石墨、Al粉、Si粉为原料,固定板状刚玉、α-Al2 O3微粉、石墨的加入质量分数分别为85％、5％、2％,加入8％(w)不同比例的Al粉和Si粉(Al、Si质量比分别为0∶8、5∶3、3∶5和8∶0),以酚醛树脂为结合剂,制备了低碳Al2O3-C滑板,并研究了该滑板材料于1 500℃保温3h埋石墨热处理后的热态抗折强度、应力-应变关系和抗热震性,同时分析了其物相组成和显微结构.结果表明,此低碳Al2O3-C滑板材料具有较高的高温强度和优良的抗热震性:当Al、Si质量比从0∶8变为8∶0时,材料在1 400℃的高温抗折强度从10.4 MPa增至32.4 MPa;在6.5 MPa载荷下1 400℃时的最大变形量从215 μm降至90 μm;1 100℃(≒)风冷热震3次后的抗折强度保持率从80％降至65％.这是由于Al、Si在使用的高温下与C、CO和N2反应生成了非氧化物Al4C3、AlN和SiC,这些非氧化物填充在刚玉骨架结构中起增强、增韧作用,有利于提高低碳Al2O3-C滑板材料的高温力学性能.
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