摘要
采用热压注工艺成型氧化硅基陶瓷型芯。分析焙烧后型芯的化学成分、微观结构、孔隙率、线膨胀系数以及力学性能。结果表明:型芯的孔径呈多峰分布,且主要分布在0.1～5μm之间;从室温至1400℃,型芯的线膨胀系数随温度的升高而减小,在1170～1350℃之间其线膨胀系数下降趋势骤然加剧;经1200℃焙烧制备的陶瓷型芯主晶相为β-方石英相与无定形石英玻璃共存,经1550℃高温2h处理后型芯烧结程度提高,骨架致密度增大,孔结构更加分明,表面及内部裂纹的数量、长度均增大。采用实验室自制的硅基陶瓷型芯进行镍基高温合金单晶空心叶片的浇注实验,结果表明所制备的型芯可以满足单晶叶片精密铸造的要求。
The silica based ceramic cores were formed by hot pressure molding method. The composition, porosity, expansion coefficient, microstructure and mechanical property of the sintered ceramic cores were characterized. The test results show that the pores of the ceramic cores are distributed in multiple peaks, and mainly locate from 0. lμm to 5μm. With the temperature increasing to 1400℃ , the expansion coefficient is decreased and the downtrend is suddenly intensified between 1170℃ and 1350℃. The 13-cristobalite phase and amorphous quartz coexist in the ceramic cores sintered at 1200℃. Heated at 1550℃ for 2h, the compactness of the ceramic cores increases, and the pore structure is more distinct, furthermore, both the quantity and the length of the cracks at the exterior and interior of the ceramic cores increase. Besides, the nickel-based alloy hollow blade was casted using the ceramic cores manufactured at the temperature of 1550% successfully.
出处
《航空材料学报》
EI
CAS
CSCD
北大核心
2013年第4期1-8,共8页
Journal of Aeronautical Materials
基金
上海"科技创新行动计划"(08dj1400400)
关键词
陶瓷型芯
单晶叶片
抗弯强度
高温蠕变
ceramic cores
single-crystal blade
flexural strength
high-temperature creep
