摘要
用BaCO_3、ZrO_2和CaO混合粉料,在1400℃经高温固相反应合成了BaZrO_3和CaO掺杂BaZrO_3粉料,采用冷等静压结合固相烧结技术,在1750℃烧成BaZrO_3和CaO掺杂BaZrO_3坩埚,并熔炼Ti2Ni合金,研究了CaO对BaZrO_3坩锅微观组织及其与钛合金界面反应的影响。结果表明:掺杂量为15%(摩尔分数)的CaO部分固溶进BaZrO_3,坩埚在烧成过程中,过量CaO部分在坩埚内部团聚,阻碍Ba_(1-x)Ca_xZrO_3晶粒的生长,导致坩埚内部出现较大孔洞;另一部分在坩埚壁析出,析出层主要由CaO和Ba_(1-x)Ca_xZrO_3组成,厚度约为70μm。BaZrO_3坩埚与钛合金界面反应层厚度约为270μm,而CaO掺杂BaZrO_3坩埚与合金并无明显界面反应层。
Abstract： CaO-doped BaZrO3 and BaZrO3 powders were synthesized by a solid-state method at 1 400 ℃ with BaCO3, ZrO2 and CaO powder as starting materials, and subsequently titanium alloys were melted in two crucibles that were prepared with the synthesized powders by cold isostatic pressing and solid-state sintering at 1 750 ℃, respectively. The effect of CaO additive on the microstructure evolution of BaZrO3 crucible and the interracial reaction with titanium alloys was investigated. The results show that a part of CaO salutes into BaZrO3, and the excessive CaO gathers together in sintering process, hindering the sintering of Ba1-xCaxZrO3 grains and resulting in massive big pores in the crucible. A precipitation behavior of CaO in the crucible wall occurs, and this precipitation layer is mainly composed of CaO and Ba1-xCaxZrO3 with the thickness of approximately 70 μm. The erosion thickness of BaZrO3 crucible is 270 μm, and little interfacial reaction between titanium alloys and CaO-doped BaZrO3 crucible occurs.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2017年第9期1354-1359,共6页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(51374142)
国家"973"计划(2014CB643403)
上海市科委基金(14JC1491400)资助
关键词
锆酸钡
氧化钙
掺杂
钛合金
界面反应
barium zirconate
calcite
doping
titanium alloy
interracial reaction
