稀土氧化镨对氧化镁陶瓷性能的影响

Effects of Praseodymium Oxide on Properties of Magnesia Ceramics

为探究添加不同质量分数的稀土氧化镨(Pr_(6)O_(11))对氧化镁(MgO)陶瓷材料烧结、硬度及抗热震性能的影响,采用MgO粉末为原料,Pr_(6)O_(11)作为添加剂,聚乙烯醇(PVA)为黏结剂,干压成型后常压烧结制得氧化镁陶瓷材料;其成型烧结温度为1580℃并保温3 h,然后检测MgO陶瓷的物相、烧结性能、硬度、表面形貌及抗热震性能。结果表明:Pr_(6)O_(11)对MgO陶瓷材料的烧结性能(密度和收缩率)有一定增强效果但增幅不大,而对MgO的硬度和抗热震性增强效果显著;当稀土Pr_(6)O_(11)的添加量为8%时,MgO陶瓷的洛氏硬度和抗热震次数最高,分别为60.1 HRA和17次。

Magnesia ceramics is made from magnesium oxide(MgO)powder as raw material,rare earth praseodymium oxide(Pr_(6)O_(11))as additive,and polyvinyl alcohol(PVA)as binding agent,through dry-pressing molding and pressure⁃less sintering methods.We investigated the crystal phase,sintering properties,hardness,morphology and thermal shock resistance properties of MgO ceramics,which was made at the sintering temperature of 1580℃for 3 h.The Pr_(6)O_(11) was added for investigation into the effect of different contents of RE oxides on sintering,hardness,and thermal shock resis⁃tance of MgO ceramics.The results showed that the Pr_(6)O_(11) had certain enhancement effect on the sintering properties(density and shrinkage ratio)of MgO ceramics but not very much;however,the hardness and thermal shock resistance of MgO were significantly enhanced,and when the added Pr_(6)O_(11) content was 8%,MgO ceramics enjoys the optimal hard⁃ness and thermal shock resistance properties,which were 60.1 HRA and 17 times,respectively.