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I am currently enrolled at University of Nebraska-Lincoln. The main courses I've taken in Solid Mechanics are Continuum Mechanics and Advanced Finite Element Method (currently taking). My undergraduate and Master major is Civil Engineering, both obtained in my home country Brazil. I would say that my strength related to this course is my motivation to understand the complex physical process of cracking, and my weakness is probably the fact that I don't have a good background in Fracture Mechanics. I am curretly pursuing my PhD at UNL under supervision of Dr. David Allen. Unfortunately our group doesn't have a published website. I am currently working on the development of a multi-scale computational model for predicting the evolution of damage in composites subject to impact loading. So, a better understanding of fracture mechanics and of the physical process underlying cracking will be of major importance to my research work. Finally, as fracture mechanics is present in any engineering application, I am sure it will greatly improve my education in a general basis.

• Various cracks in thin films under tensile or compressive stresses
• Micrographs of cracks in thin films
• A micrograph of a channel crack
• The origin of stress in a film
• Stress in a thin film due to mismatch in the coefficients of thermal expansion
• Stress in film due to bending
• Measure redisual stress using wafer curvature
• Channel crack:  initiation vs. steady propagation
• Steady-state energy release rate of a channel crack
• Channel crack in patterned structure

Calculating stresses in MD simulations is a controversial topic. There are two different schools of thought about the equivalence of the virial stress to the continuum Cauchy stress; for and against. Some argue based on momentum balance, that only the potential contribution to the virial stress should be considered as the continuum Cauchy stress. However, others assert that the total virial stress that contains both the kinetic and potential parts is indeed the quantity that corresponds to the Cauchy stress in continuum mechanics. We used a simple thermo-elastic analysis to verify the validity of using the total virial stress as the continuum Cauchy stress and found that the total virial stress is indeed the continuum Cauchy stress.

Hi

I have an investigation on Crack Propagation.

How can i predict the path of a crack.

Please help me!

Lecture 5