Simulation of Indentation Fracture in Crystalline Materials Using Mesoscale Self-Assembly

详细信息    查看全文

• 作者：Venkat R. Thalladi ; Alexander Schwartz ; Jennifer N. Phend ; John W. Hutchinson ; and George M. Whitesides
• 刊名：Journal of the American Chemical Society
• 出版年：2002
• 出版时间：August 21, 2002
• 年：2002
• 卷：124
• 期：33
• 页码：9912 - 9917
• 全文大小：1281K
• 年卷期：v.124,no.33(August 21, 2002)
• ISSN：1520-5126

文摘

A new physical model based on mesoscale self-assembly is developed to simulate indentationfracture in crystalline materials. Millimeter-scale hexagonal objects exhibiting atom-like potential functionswere designed and allowed to self-assemble into two-dimensional (2D) aggregates at the interface betweenwater and perfluorodecalin. Indentation experiments were performed on these aggregates, and the stressesand strains involved in these processes were evaluated. The stress field in the aggregates was analyzedtheoretically using the 2D elastic Hertz solution. Comparison of the experimental results with theoreticalanalysis revealed that fracture develops in regions subjected to high shear stress and some, albeit low,tensile stress. The potential for the broader application of the model is illustrated using indentation ofassemblies with point defects and adatoms introduced at predetermined locations, and using a two-phaseaggregate simulating a compliant film on a stiff substrate.