摘要
声发射技术是理论落后于实践的少数学科之一。为了建立力学参数与声发射参数之间的关系,对ST13板材的拉伸过程进行声发射动态监测试验,得到声发射能量累积曲线与应力-应变曲线的变化关系。结合晶体位错运动理论分析材料变形过程中的声发射特性。试验结果表明:在整个屈服过程中,均伴有高能量的声发射信号,随着加工硬化的增加,声发射信号不断减少,在断裂瞬时,再次出现高能量的声发射信号;声发射能量累积曲线能较好地表征ST13板材内部损伤演化的全过程。用声发射能量累积值定义损伤变量,基于声发射参数与损伤变量的一致性观点,通过Weibull分布函数建立声发射能量累积值与应力-应变之间的耦合关系。
Acoustic emission technology is one of the few subjects whose theory is behind practice. In or- der to investigate the relationship between mechanical parameters and AE parameters, a tensile test of ST13 plate was conducted by taking AE technology dynamic monitoring the process, obtained the relation- ship between the AE energy accumulation curve and stress-strain curve. Based on crystal dislocation mo- tion explained the AE features during material deformation. Analysis showed that： during the whole yield process, were accompanied by the high-energy AE signals~ with the increase of hardening, AE signals de- creased; in the fault transient, appeared high-energy AE signals again. The AE energy accumulation curve could be used to describe the whole process of the evolution of internal damage. Using AE cumula- tive energy defined the damage variable. Correlated with the consistency between AE parameters and damage variable established the coupling relation between AE energy cumulative value and stress-strain by Weibull distribution function.
出处
《力学季刊》
CSCD
北大核心
2012年第1期10-14,共5页
Chinese Quarterly of Mechanics
基金
江西省研究生创新专项资金(YC10A034)
