摘要
针对凝胶注模制备大尺寸空心涡轮叶片陶瓷铸型产生的颗粒偏析导致铸型均匀性降低、烧结产生变形甚至开裂等问题,以铸型高度方向上的密度变化为评价指标,主要研究了颗粒级配、固相含量、球磨时间、振动等因素对于铸型颗粒偏析的影响,并利用样品粒度分布和微观结构进行佐证。结果表明:当颗粒级配为40μm/5μm、固相体积分数为60%、浆料球磨时间为60min、充型时施加振动频率为60Hz、幅值为3mm时,陶瓷铸型密度梯度最小。成功制备了高度为150mm、上下密度梯度仅为0.89%(密度差异值为0.018g/cm3)的均匀陶瓷铸型,完全满足大尺寸空心涡轮叶片陶瓷铸型的均匀性要求。
In fabricating ceramic casting mold of hollow turbine blades, particle segregation usually weakens the mold homogeneity leading to deformation and cracking as sintering. The variety trend of density along casting mold height is regarded as the evaluating index, the effects of grain gradation, solid content, milling time, validation etc on particles segregation are discussed and verified by the size distribution and microstructures. The results show that taking the grain gradation as 40μm/5 μm, solid volume fraction as 60~, milling time as 60 min, filing vibration frequency as 60 Hz, with amplitude of 3 mm, the casting mold density gradient reaches the smallest. The homogeneity casting mold with height of 150 mm, density gradient of 0.89% （variety of density 0. 018 g/cm3） is successfully prepared to completely satisfy the homogeneity requirements of large-size ceramic casting mold of the hollow turbine blades.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2014年第10期77-83,共7页
Journal of Xi'an Jiaotong University
基金
国家重点基础研究发展计划资助项目(2013CB035703)
中央高校基本科研业务费专项资金资助项目
关键词
颗粒偏析
密度梯度
空心涡轮叶片
凝胶注模
particle segregation
density gradient
hollow turbine blade
gel-casting
