EVALUATING THE INFLUENCE OF PLASTIC DEFORMATION TO THE DAMAGE SUSCEPTIBILITY OF MATERIALS FROM THE NATURE OF FATIGUE-STRENGTH CHANGE,

Abstract

The effect of preliminary tensile deformation on the fatigue strength of ferrous and nonferrous materials is examined. Samples were fatigue tested in pure shear at a frequency of 3000 cycles/min. The endurance limit was arbitrarily selected as 5,000,000 cycles. After undergoing plastic deformation in tension, some samples had their surfaces machined off to a depth of 0.2-0.3 mm. Before fatigue testing, all surfaces were polished with a rubber wheel. Microhardness tests along the cross section and near the surface showed no change in hardness after machining. The ratio of endurance limit at any tensile strain to that at zero strain was used to determine the effect of plastic deformation. The fatigue strength of type 35 steel in the normalized and tempered (650C) condition is given as a function of the number of cycles to failure. (Author)

Document Details

Document Type
Technical Report
Publication Date
Feb 03, 1969
Accession Number
AD0694797

Entities

People

  • T. K. Marients
  • V. A. Zhukov

Organizations

  • National Air and Space Intelligence Center

Tags

DTIC Thesaurus Topics

  • Cyclic Loads
  • Fabrication
  • Frequency
  • Hardness
  • Machining
  • Manufacturing
  • Materials
  • Mechanical Properties
  • Microhardness
  • Physical Properties
  • Plastic Deformation
  • Tensile Strain

Fields of Study

  • Materials science

Readers

  • Metallurgy
  • Structural Health Monitoring of Composite Structures.