Materials Science and the Mechanics of Failure

Faculty Advisor: Yale PhD; Mechanical Engineering Researcher

Research Program Introduction

Materials science sits at the foundation of every engineered object, from the humble paperclip to the hull of a warship, the wing of an airliner, and the frame of a bicycle. Before any structure can be designed, an engineer must understand what the material inside it is actually doing: how its atoms and microstructure give rise to strength, why some materials bend while others shatter, and why materials fail. In this program, we will build that understanding from the ground up and then turn to one of the most consequential questions in engineering: why do things break?

We will begin with the fundamentals. We will look at how stress and strain reveal a material's character, and how its internal structure, down to the atomic scale, determines whether it is strong, tough, ductile, or brittle. From there, we will study how manufacturing processes like casting, forging, welding, and 3D printing leave their own fingerprints on a part, often setting up the very flaws that later cause it to fail.

With that foundation in place, we will examine failure itself: how stress concentrates around holes, notches, and sharp corners; how cracks form and grow under repeated loading, a phenomenon called fatigue; and how time, temperature, and corrosive environments quietly weaken materials over years of service. Along the way, we will study some of history's most instructive engineering failures, from the brittle fracture of the Liberty ships to the fatigue cracking that downed the Comet airliner.

At the end of the program, each student will complete a final project on an aspect of materials science or failure mechanics, either through a quantitative case study of a real engineering failure or through an original analysis connecting material behavior to a design decision. Either way, students will demonstrate an understanding of core materials and failure concepts.

Project Topics for Final Projects:

• Investigate a historical engineering failure, such as the Liberty ships, the Comet airliner, the Tacoma Narrows Bridge, or the Space Shuttle Challenger, and analyze the mechanism that caused it

• Compare candidate materials for a specific product (such as a bicycle frame, phone case, or surgical implant) and defend a selection based on strength, weight, and resistance to possible modes of failure

• Investigate how rapid prototyping techniques such as 3D printing produce parts that fail differently, depending on how they are printed and what they will actually be used for

• Study fatigue failure in a structure or vehicle of your choice, and how engineers may design against it

• Other topics approved by the Faculty Advisor

Program Detail

• Cohort size: 3 to 6 students

• Workload: Around 4 to 5 hours per week (including class and homework time)

• Target students: 9-12th grade students who are interested in Materials Science, Engineering, Physics, Chemistry, Industrial Design, or other related areas.

• Schedule: TBD. Meetings will take place for around one hour per week, with a weekly meeting day and time to be determined a few weeks before the class start date.