摘要
在 12 5 0℃ ,5 0MPa应力条件下 ,通过三点弯曲试验方法研究了复相BAS玻璃陶瓷的蠕变行为。试验结果表明 ,在稳态蠕变阶段 ,试样压头位移速率是 0 .0 0 5 89mm /h .利用由弹性变形理论导出的方程计算出应力指数为 0 .6 31、稳态蠕变速率小于 1.0 33× 10 -4 /h。这表明蠕变由扩散控制 ,稳态蠕变速率比其它类型玻璃陶瓷小得多。在蠕变过程中 ,具有晶粒大小约 0 .5 μm细晶结构的复相BAS玻璃陶瓷呈现晶粒团的蠕变特征 ,提高了材料抗蠕变能力。
The creep behavior of the multiphase BAS glass-ceramics has been investigated by 3-piont bending test at 1250℃ under a stress of 50MPa.The results show that the crosshead displacement rate of the BAS glass-creamics is 0.00589mm/h during steady-state creep;The stress exponent is estimateted to be 0.631 and the steady-state creep rate is calculatedas as <1.033×10 -4 ·h -1 by using the equations deduced form the elastic deformation theory. They show that the diffusion controls the creep behavior of the glass-ceramics and its creep rate is very low under the experiment condition.The microstructure evaluation reveals that the fine grais with a grain size of 0.5μm in the glass-ceramics form clusters during the creep.Thus ,the clusters act as coarse grains and result in good creep resistance.
出处
《兵器材料科学与工程》
CSCD
北大核心
2000年第5期13-17,共5页
Ordnance Material Science and Engineering
关键词
钡长石
玻璃陶瓷
应力指数
稳态蠕变速率
barium feldspar, glass-ceramics,stress exponent, steady-state creep rate
