摘要
本文对添加30wt％ZrSiO_4硅基型芯试样在1200～1600℃时的热变形,抗弯强度、收缩率和型芯溶蚀性进行了研究。结果表明:在1550℃的热变形量激增,1350～1400℃的抗弯强度突降,前者因Al_2O_3与SiO_2形成的液相,后者主要与石英玻璃的大量析晶有关,收缩率随温度升高而增加而型芯溶蚀速度减小,是与型芯组织内的粘滞流动导致微观相之间孔隙减小,气孔率下降有关。
The silica-base core for directionally solidified air-cooled blade is composed of 30wt% ZrSiO_4 and 70wt% quartzo.The higth temperature deformation, bending strength, contraction and corrosion rate of the core specimens were measured in the temperature range of 1200-1600℃,the results show that with the rise of temperature the contraction trate increases but the corrosion rate decreases mainly due to the variation of the viscous flow of core. The gap between the particles of core decreases,that makes the contraction rate increase. Because of the drop of microporosity. Therefore, corrosion rate becomes slower gradually. The dramatic increases of high temperature deformation around 1550℃ is mainly resulted from the formation of liquid phase (compound of Al_2O_3 and SiO_2),the remarkable impairment of bending strength between 1350—1400℃ is mainly due to a great deal of quartz transferring into crystalline state.
出处
《铸造技术》
CAS
北大核心
1992年第1期11-15,共5页
Foundry Technology
