耐火材料 ›› 2021, Vol. 55 ›› Issue (1): 35-39.DOI: 10.3969/j.issn.1001-1935.2021.01.008

• 研究开发 • 上一篇    下一篇

不同Al2O3含量镁铝尖晶石材料高温力学性能研究

范沐旭(), 石干(), 张伟   

  1. 中钢集团洛阳耐火材料研究院有限公司 河南洛阳 471039
  • 收稿日期:2020-06-15 出版日期:2021-02-15 发布日期:2021-02-15
  • 通讯作者: 石干,男,1956年生,硕士,教授级高级工程师。E-mail: shigan@yeah.net
  • 作者简介:范沐旭:男,1990年生,硕士。E-mail: 404913797@qq.com

Effect of Al2O3 content on hot mechanical properties of magnesium aluminate spinel

Fan Muxu(), Shi Gan(), Zhang Wei   

  1. Sinosteel Luoyang Institute of Refractories Research Co.,Ltd.,Luoyang 471039,Henan,China
  • Received:2020-06-15 Online:2021-02-15 Published:2021-02-15
  • Contact: Shi Gan

摘要:

研究了Al2O3含量(w)分别为66%、71%、75%、85%、90%的高纯烧结镁铝尖晶石材料和不同Al2O3含量的电熔再结合镁铝尖晶石材料的热态抗折强度、压蠕变特性、显微结构等。结果表明:1)对于高纯烧结镁铝尖晶石材料,随着Al2O3含量的增大,其热态抗折强度都有所增大。Al2O3含量为66%(w)的试样是尖晶石-方镁石复相材料,方镁石的存在弱化了晶界结合力,高温强度较小。Al2O3含量(w)分别为71%、75%、85%的试样,随着Al2O3含量的增大,晶粒尺寸变大,晶界结合力增强,断裂方式由沿晶断裂为主过渡到穿晶断裂为主,高温强度也随之增大。Al2O3含量为90%(w)的试样为尖晶石-刚玉复相材料,导致其高温强度低于Al2O3含量为85%(w)的试样的。2)电熔再结合镁铝尖晶石试样的烧结性随着Al2O3含量的增加而减小,抗蠕变性随着Al2O3含量的增加而增大。

关键词: 镁铝尖晶石, 非化学计量, 热态抗折强度, 抗蠕变性

Abstract:

The hot modulus of rupture,the creep resistance and the microstructure of high purity sintered MgAl2O4 materials with 66%,71%,75%,85%,and 90% Al2O3 (by mass) and fused-rebonded MgAl2O4 materials with varying Al2O3 contents were studied.The results show that:(1)for high purity sintered MgAl2O4 materials,the hot modulus of rupture increases along with the increase of the Al2O3 content;the sample with 66 mass% Al2O3 is spinel-periclase composites in which the existence of periclase weakens the bonding force of grain boundaries,thus resulting in low hot strength;for the samples with 71%,75%,and 85% Al2O3,with the increase of the Al2O3 content,the grain size increases,and the bonding strength of grain boundaries increases,the main fracture mode changes from intergranular fracture to transgranular fracture,and the hot strength also increases;the sample with 90% Al2O3 is spinel-corundum composite which leads to lower hot strength than that of the sample with 85% Al2O3;(2)the sinterability of the fused-rebonded MgAl2O4 materials decreases with the increase of the Al2O3 content,while the creep resistance increases.

Key words: magnesium aluminate spinel, non-stiochiometry, hot modulus of rupture, creep resistance

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