Post-Overload Fatigue Crack Recovery in Powder Metal Aluminum-Lithium AL-905XL Forging

Abstract

An overload fatigue investigation was conducted to determine whether variation in the relative humidity would effect the post-overload retardation recovery period of a dispersion hardened powder metal aluminum, alloy AL905XL forging. Constant amplitude and single spike overload tests were conducted in laboratory air, and in low and high humidity air environments. Post-overload crack opening load and crack propagation velocity were observed to determine the number of delay cycles required for the velocity and crack opening load to return to the values immediately preceding overload. Crack retardation increased in the high humidity environment and for shorter crack lengths attributable to increased crack closure.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1991
Accession Number
ADA232550

Entities

People

  • Russell R. Cervay

Organizations

  • University of Dayton

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Aluminum Alloys
  • Corrosion Resistance
  • Crack Tips
  • Dynamic Loads
  • Engineering
  • Environment
  • Fatigue Tests (Mechanics)
  • High Humidity
  • Low Humidity
  • Materials
  • Materials Engineering
  • Materials Laboratories
  • Metals
  • Powder Metals
  • Procurement
  • Stress Corrosion
  • Universities

Readers

  • Mathematics or Statistics
  • Metallurgy
  • Structural Health Monitoring of Composite Structures.