FATIGUE CRACK PROPAGATION AND FRACTURE STUDIES OF A PRESSURE VESSEL STEEL TEMPER EMBRITTLED TO SIMULATE IRRADIATION DAMAGE.

Abstract

Fatigue crack propagation tests were conducted using plate bend specimens machined from shell material of the PM-2A half-scale model pressure vessel. The material is a Cr-Mo-V rotor steel, temper embrittled to represent the irradiated shell of the PM-2A reactor vessel. The fatigue tests were conducted in a room-air environment at 80 F, which is 160 F below the NDT (nil-ductility transition) temperature for this steel. Fatigue crack growth rates were correlated with total strain range, and were found to be similar to fatigue crack growth rates in other structural steels which possess comparable yield strength levels. Fracture occurred in the plate bend specimens of the test material during fatigue cycling. This represents a significant departure from the behavior of previously studied structural steels, and is attributed to the very high NDT temperature of the test material. An analysis of the fractures using an approximate solution for the stress-intensity factor, K, gave good agreement with previous plane strain fracture toughness measurements on the test material. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1967
Accession Number
AD0663133

Entities

People

  • E. A. Lange
  • L. A. Cooley
  • Thomas W. Crooker

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Crack Propagation
  • Cracks
  • Fatigue Tests (Mechanics)
  • Materials
  • Measurement
  • Pressure Vessels
  • Scale Models
  • Steel
  • Stress Intensity Factors
  • Structural Steel
  • Transitions
  • Yield Strength

Fields of Study

  • Materials science

Readers

  • Materials Science (Mechanical Engineering).
  • Structural Dynamics.