摘要
本文作者研究了 6 0 0℃水淬和 6 0 0℃退火处理的碳化硅晶须增强铝基复合材料的热膨胀行为 ,阐述两者热膨胀行为与内应力的内在关系。结果表明 :淬火后复合材料基体的位错密度、内应力、及材料的有效屈服强度较高 ;而退火后复合材料基体的位错密度、内应力、及材料的有效屈服强度较低。当材料在 6 0 0℃淬火后 ,升温过程中材料的热膨胀系数曲线在 80℃和 2 4 5℃各出现一个峰值 ,且后者明显高于前者 ;而 6 0 0℃退火后材料的热膨胀系数曲线只在 80℃出现一个波峰 ,且其峰值低于淬火材料相应的峰值。分析表明 :材料热膨胀系数曲线出现的第一个峰是基体内拉应力释放的结果 ;
This paper deals with the relationship between thermal expansion behaviors and internal stresses of SiC W/Al composites quenched from 600℃ by water and annealed from 600℃ with a cooling rate of 1℃/min. The results show that the dislocation density, residual tensile stress in the matrix and yield strength of the quenched composite are larger than those of the annealed composite. There are two peaks on the curve of the coefficients of thermal expansion (CTE) vs heating temperature of the quenched composite. The first peak appears at about 80℃, and the second one appears at 245℃, and the latter is much higher than the former. But only one peak appears at 80℃ on the curve of the CTEs vs temperature of the annealed composite, and the peak is smaller than the first one of the quenched specimen. The CTE of the annealed specimen increases with temperature increasing gradually. The first peak on the curve of CTE vs temperature is the result of relaxation of the residual tensile stress in the matrix, while the second one is a signal of the relaxation rate of the compressive stress in the matrix of the composite.
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2002年第5期57-61,共5页
Acta Materiae Compositae Sinica
基金
国家自然科学基金的资助
项目编号为 5 963 10 80
