fracture mechanics
Interfacial toughness and mode mixity
When I was a graduate student, I spent several months to measure interfacial toughness between metalic (Cu and Au) films and thick substrates(Si and Polycarbonate). My methods were bulge test (blistering test) and 4-point bending test. I had many problems such as making an initial crack(pre-cracking), changing load phase angle applied to specimens, preparing/patterning thin films, constructing my own test apparatus, etc. The biggest problem was to measure the interfacial toughness over a wide range of loading phase angle. For a bimaterial with a non-zero oscillatory index(epsilon), we don't know the phase angle for a minimum interfacial toughness beforehand. Therefore, we need to measure the interfacial toughness over a wide range of phage angle. For engineering purpose, we need a minimum interfacial toughness value for reliability design because this value will lead to a conservative design of systems.
Homework 1, problem 1 - Self description
I'm Francisco Thiago S. Aragao. Please call me Thiago. I'm currently enrolled at the University of Nebraska at Lincoln Civil Enginering Master's Program under the advisory of Dr. Yong-Rak Kim. I have also a minor course in Engineering Mechanics. Below I'm answering the questions from the Problem 1 of Fracture Mechanics' Assignment 1.
Prior courses in solid mechanics:
C.H. Wang, "Introduction to Fracture Mechanics"
Here is a link to a 1996 book by C.H. Wang on Fracture Mechanics from the DSTO Aeronautical and Maritime Research Laboratory in Melbourne.
http://www.dsto.defence.gov.au/publications/1880/DSTO-GD-0103.pdf
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