Spring 2007

My name is Nanshu Lu. I am a second year doctoral student in the Suo group at Harvard Engineering and Applied Science.

I obtained my B.S. in Solid Mechanics from the Department of Engineering Mechanics at Tsinghua University, China. You can see my resume here.

My course background includes Strength of Materials, Continuum Mechanics and Fundamental Elasticity taken at Tsinghua University and graduate level Elastisity (ES 240) taught by Prof. J. Rice, Deformation of Solids (APY 293) taught by Prof. F. Spaepen, Fracture (ES 247) and Plasticity (ES 246) taught by Prof. J. Vlassak and Zhigang's another course Advanced Elasticity (ES 241) this semester here at Harvard.

My first teaching experience was TFing Zhigang's ES 240 last semester.

Although I think I've indulged in a systematic cognition of solid mechanics with somewhat solid understanding of this subject, I sometimes do lack a spirit of digesting materials and making them my own. It indeed has occured to me that having a hard time to fish out the proper solution to a novel problem although I've owned all the needed tools and skills. Under the instruction of John and Zhigang I hope I will make the transformation from a student learner to a scholar learner.

Nonlinear fracture mechanics joints main parts of solid mechanics: fracture, elasticity and plasticity, the essential foundation to my research interests of mechanics in thin films, both theories and experiments. One of my subject is about chip packaging interaction. It is well known that nowadays a typical electronic package assembly consists of different materials which are attached together in a variety of ways. No other course will be more proper for this subject than this "Fracture mechanics of thin films and composit materials". Though I've read literatures specialized on thin film debonding I believe taking this course is the most efficient way for me to have profound and comprehensive understanding of fracture mechanics as a whole.

I am Namiko Yamamoto, a 1st year PhD student in Aero/Astro department at MIT. I have been Aero/Astro major for both my BS and MS at MIT, also. I have taken ES240 (solid mechanics) with Prof. Suo this past fall, and have taken one solid mechanics class (2.071) at MIT. This is my first time learning about fracture mechanics. My weakness is that I don't know the material well, and even now I need to spend good time to understand the materials given in the lecture (notes and lectures are so helpful). My strength will be my motivation to learn the materials. It has been much fun in the class, and this learning will help me much in my research. For my PhD, I will be studying how to strengthen structural composites with carbon nanotubes (CNTs) under Professor Brian Wardle. In the current design, we will be investigating delamination fractures between prepregs. This class will be so helpful for this research, and further since I want to continue studying in materials/structure field beyong PhD.

Hi, I am Roberto Soares and I am a PhD student in Engineering Mechanics at UNL. My undergrad is from Brazil in Civil Engineering (Federal University of Ceara) and my Master’s in Engineering Mechanics from UNL. In the past I had the chance to take Continuum Mechanics, Adv Mechanics of Materials, FEM and several courses in Materials.

So far we have been mainly concerned with systems of a single independent variable: energy (node/4878). We now consider a system of two independent variables: energy and volume. A thermodynamic model of the system is prescribed by entropy as a function of energy and volume.

The partial derivatives of the function give the temperature and the pressure. This fact leads to an experimental procedure to determine the function for a given system.

The laws of ideal gases and osmosis are derived. The two phenomena illustrate entropic elasticity.

Hi everyone. My name is Michael Mahoney and I'm currently enrolled in the fracture mechanics course at the University of Nebraska. I am pursuing my master's degree in engineering mechanics. My advisor is Dr. Joseph A. Turner and my research is in acoustoelastic methods for characterizing stress in a material. Here is a link to our research group:  http://em-jaturner.unl.edu/.

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

Lecture 5

Lecture 5

Lecture 4