Accession Number : AD0848453

Title :   Evaluation of Three Point Fatigue-Cracked Bend Test Parameters.

Descriptive Note : Final rept. Oct 67-Mar 68,

Corporate Author : DAYTON UNIV OH RESEARCH INST

Personal Author(s) : Petrak, Gerald J.

Report Date : NOV 1968

Pagination or Media Count : 23

Abstract : A recommended practice for three point slow bend plane strain fracture toughness testing is currently being prepared by ASTM-E-24. To insure maximum reproducibility and accuracy of fracture toughness results, necessary strict tolerances on testing parameters are being incorporated into this practice. Previous to this report, a systematic test evaluation program to determine the effect of variation in two of these test parameters had not been conducted. This program was conducted to establish the effect of variation in the straightness of the fatigue crack front and the location of the knife edges for the attachment of the crack opening displacement gage on the slow bend specimen. Double size specimens were tested to insure the accuracy of the KIC measurements. The results indicated no effect of knife edge mislocation up to 0.050 inches offset and no effect of crack front straightness for the material tested. (Author)

Descriptors :   (*ALUMINUM ALLOYS, FATIGUE(MECHANICS)), (*TEST METHODS, STANDARDIZATION), TENSILE PROPERTIES, YIELD POINT, ELONGATION, CRACK PROPAGATION, DUCTILE BRITTLE TRANSITION, BENDING, RUPTURE, TOLERANCES(MECHANICS).

Subject Categories : Metallurgy and Metallography
      Test Facilities, Equipment and Methods
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE