FATIGUE TECHNOLOGY

Grace Hung, Claire Kaiser, Derek Tantisalidchai, Gene Yoon, Joseph

Myers

Introduction

Fatigue Technology Inc. (FTI) tests aeronautic materials, develops strengthening and prevention techniques, and manufactures fasteners

Our Task To analyze the effects on fatigue life if the

load on a hypothetical airplane was increased

Two dog bone coupons were tested; one under 25ksi and one under 30ksi oscillating at 15 hertz

Data

Load: increased from 30,000 lbs to 35,000 lbs, +16.6667%

Fatigue Life: decreased from 15,382 cycles to 10,268 cycles, -33.247%

Conclusion

To determine if the increase in load is safe, the designers of the airplane would have to determine if the reduction in stress life is at an acceptable level. If not, then a thicker material would have to be used.

Preventative Measures

FTI has developed a process of cold working the interior of high stress holes by compressing the surrounding material

FTI also produces specialized bushings and grommets that also incorporate this technology

Special Thanks to Len Reid, David Larson and Fatigue Technology Inc!