HIGH-CYCLE FATIGUE
AND TIME-DEPENDENT FAILURE IN METALLIC ALLOYS FOR
PROPULSION SYSTEMS
AFOSR-MURI HIGH-CYCLE FATIGUE PROGRAM
Grant No. AFOSR F49620-96-1-0478
Robert O. Ritchie, PI1
Subra Suresh, Co-PI2
John W. Hutchinson, Co-PI3
Walter W. Milligan, Co-PI4
Anthony W. Thompson1
1Department of Materials Science and Mineral Engineering
University of California
Berkeley, CA 94720-1760
2Department of Materials Science and Engineering
Massachusetts Institute of Technology
Cambridge, MA 02139
3Division of Applied Sciences
Harvard University
Cambridge, MA 02138
4Department of Metallurgical and Materials Engineering
Michigan Technological University
Houghton, MI 49931
THIRD PROGRESS REPORT FOR THE PERIOD 10/1/98 – 8/31/99
Air Force Office of Scientific Research
AFOSR/NA
801 N. Randolph Street, Rm 732
Arlington, VA 22203
September 1, 1999
AFOSR-MURI Program
on High-Cycle Fatigue
High-Cycle Fatigue
and Time-Dependent Failure in Metallic Alloys for
Propulsion Systems
R.O. Ritchie (PI)1
S. Suresh,2 J.W. Hutchinson,3 W.W. Milligan,4 A.W. Thompson1
1University of California, Berkeley
2Massachusetts Institute of Technology
3Harvard University
4Michigan Technological University
AFOSR-MURI Program
Grant No. AFOSR F49620-96-1-0478
Major Brian Sanders, Program Manager
TABLE OF CONTENTS
Cover Pages
Table of Contents
I. Objectives
II. Executive Summary of Status of Effort
III. Research Summary of Individual Projects
A. Lower-Bound HCF Thresholds in Ti-6Al-4V
B. Mixed-Mode Fatigue-Crack Threshold in Ti-6Al-4V
C. Influence of Foreign Object Damage on Fatigue of Ti-6Al-4V
D. Residual Stress Measurements of Foreign Object Damage
E. High-Cycle Fatigue of Nickel-Base Superalloys
F. Modeling and Experimental Studies of Fretting Fatigue
G. Theoretical Studies of Fatigue and Fretting
IV. Personnel
V. Publications
VI. Transitions and Other Interactive Activities