摘要
采用动态力学分析仪(DMA)研究了温度、降温速率、低温保护剂对冻结状态下兔胸主动脉的裂纹扩展和断裂模式的影响。研究结果表明:随着温度的降低,主动脉轴向由典型的韧性断裂转变为典型的脆性断裂,并且其裂纹扩展也越困难;降温速率对冻结状态下主动脉的裂纹扩展和断裂模式影响不大;DMSO对主动脉的冻结过程有明显的"软化"作用,裂纹更容易扩展,而且呈现出典型的韧断;均以5℃/min降温到-50℃后,血管周向比轴向易于扩展,但其与轴向试样表现出截然相反的典型韧断,这充分说明冻结状态下主动脉仍然体现出各向异性的特点。
The effect of temperature, cooling rate, and cryopretective agent （CPA） on the crack growth and fracture modes of frozen rabbit aorta have been conducted by Dynamical Mechanics Analysis （DMA）. The results show that： The lower the temperature, the more difficulty the crack growth of frozen rabbit aorta, and the fracture modes are also transformed from typical ductile fracture to typical brittle fracture with temperature decreasing. The cooling rate presents little effect on the crack growth and fracture mode of frozen rabbit aorta. Due to the marked hydration action of dimethyl sulphoxide（DMSO）, the samples permeated by 10%（V/V） DMSO exhibit a kind of typical ductile fracture mode and the crack growth is also easier. After cooled to -50℃ at the cooling rate of 5℃/min, crack growth of the peripheral is easier than the axial one, and fracture mode of the former is typical ductile fracture, which indicates that the mechanical properties of frozen rabbit aorta still present the characteristics of anisotropy.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2008年第1期133-135,共3页
Journal of Engineering Thermophysics
基金
国家自然科学基金重点资助项目(No.50436030)
上海市教委青年发展基金(No.F50122)
上海理工大学博士启动基金(No.X642)
关键词
主动脉
冻结
韧性断裂
脆性断裂
裂纹扩展
rabbit aorta
freezing
ductile fracture
brittle fracture
crack growth
