Anomalies of monoscale notion of failure in contrast to multiscale character of failure for physical processes
The failure problem remains undefined without specifying the multiscaling or multi-dimensional aspects of the system. Three requirements, dubbed as where-when-how, are needed. They refer, respectively, to the spatial (location), temporal (time) and failure mode (how). The absence of any one of the three can be interpreted as solution generation without a problem. Failure is a preconceived notion referring to a threshold, deviating from the norm. Anomalies and ambiguities, however, can arise when criteria based on the presumption of monoscaling are applied to multiscale systems. Micro-macro effects when analyzed using the monoscale fracture criterion of energy release rate (ERR) or the equivalent of the path independent integral can give negative results violating the First Principle. The surface energy density (SED) can reflect micro-macro effects simultaneously and remains positive. The invariant property of SED is usable for relating the microstructure properties at the different scale ranges to explain the evolution of failure. The sustainable and reliable time to assure the microstructure stability have not received the attention it deserves, particularly for the manufacturing of ultra high strength materials. This is also true for high temperature resistance nanomaterials.
Failure Energy release Surface energy density (SED) Monoscale Dualscale Multiscale Nanomaterial Sustainable Reliable Stability Compatible Surface-volume effects
G. C. Sih
International Center for Sustainability,Accountability and Eco-Affordability of the Large and Small (ICSAELS) Lehigh University,Bethlehem PA 18015,USA;Key Laboratory of Pressure Systems and Safety,Ministry of Education, East China University of Science and Technology, Shanghai 200237, China
国际会议
2012 International Symposium on Structural Integrity 2012国际结构完整性学术研讨会 ISSI 2012
济南
英文
1-7
2012-10-31（万方平台首次上网日期，不代表论文的发表时间）