摘要
采用硼砂、金属铝和碳粉为原料一步合成Al8B4C7.在合成过程中掺入不同含量的K2O,研究杂质K2O对合成Al8B4C7的影响.将原料混合均匀,在200MPa的压力下压制成φ20mm×20mm的圆柱型试样,将干燥后的试样在不同温度下的流动氩气气氛中进行合成.利用化学分析、XRD和SEM等分析测试技术,研究了K2O含量以及烧结温度对反应合成材料物相组成和显微结构的影响.结果表明:尽管加入不同含量的K2O,但其高温烧结反应后,若K2O的质量分数在0.019%～0.028%之间,就不出现含K的新相.K2O的加入不利于Al8B4C7的合成,它可将Al8B4C7的开始生成温度提升至1 400℃,而且1 700℃时,Al8B4C7含量较不加入K2O时明显减少.添加K2O合成的Al8B4C7为1μm左右大小的无规则小颗粒.
Al8B4C7 was synthesized by using borax,aluminum and carbon powders as the starting materials and adding different amount of K2O.The powders were fully mixed and then pressed into cylindrical samples with the size of φ20 mm×20 mm at 200 MPa.The samples were dried and heated at different temperatures in the flowing argon atmosphere.The effect of K2O content and the sintering temperature on the phase composition and microstructure of Al8B4C7was investigated by the chemical analysis,XRD and SEM methods.The results show that in the synthesis process of Al8B4C7,the K2O content in the sintered samples was 0.019%-0.028%,and no new phase containing K element was detected although the K2O content in the starting materials was different.K2O enhanced the formation temperature of Al8B4C7 from 1 300 ℃ to 1 400 ℃ and K2O significantly reduced the generation of Al8B4C7 at 1 700 ℃.In addition,Al8B4C7 particles showed irregular shape with the size of ~1 μm after K2O was added to the starting materials.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2011年第3期112-116,共5页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(50772079)
武汉科技大学科学基金资助项目(2008TD05)
