La_2O_3掺杂对金属陶瓷显微结构与性能的影响

Effect of La_2O_3 Doped on Microstructure and Properties of Cermets

采用冷压烧结技术制备La2O3掺杂17Ni/(NiFe2O4-10NiO)金属陶瓷惰性阳极材料,研究了La2O3掺杂对材料显微结构、烧结致密化、抗高温氧化性能及耐熔盐腐蚀性能的影响。结果表明:La2O3与陶瓷相反应生成FeLaO3相,活化了NiFe2O4晶格,促进材料的烧结致密化。适量掺杂La2O3可减少氧化膜及氧化层孔洞产生,防止出现氧化膜裂纹,提高抗高温氧化性能。La2O3掺杂的金属陶瓷通过与外界熔盐生成稳定、致密的腐蚀反应层,使基体材料得到保护,减缓腐蚀速率。La2O3掺杂量为1.0%时,腐蚀速率仅为1.336 7×10--3 g/(cm2·h)。

La2O3 doped 17Ni/(NiFe2O4-10NiO)cermet inert anodes were prepared by a cold isostatic pressing-sintering process.The effect of La2O3 doping on the microstructure,relative density,high temperature oxidation-resistance property,and corrosion resistance was investigated.The results show that NiFe2O4 lattice is activated and the process of sintering densification is promoted,causing the generation of a phase of FeLaO3.The holes of oxide film and oxide layer are decreased,and the cracks of oxide film are restrained at a proper content of La2O3.The high-temperature oxidation resistance properties of the cermets samples are promoted.The reaction between the samples surface and molten salt occurs as a stable corrosion reaction with a dense structure,which prevents the cryolite molten salt to penetrate the substrates.The corrosion rate is 1.336 7×10--3 g/(cm2·h)at La2O3 content of 1.0%.