Accession Number : AD0765329

Title :   Develop Ultrafine Grain Size Titanium with Improved Mechanical Properties.

Descriptive Note : Final rept.,

Corporate Author : FRANKLIN INST RESEARCH LABS PHILADELPHIA PA

Personal Author(s) : May,Roger C.

Report Date : APR 1973

Pagination or Media Count : 73

Abstract : Modified Kahn-type tear tests and fatigue crack propagation tests were conducted to evaluate the effect of strengthening by grain refinement and/or cold deformation on the toughness of alpha titanium. In addition to grain size and cold work, the effects of interstitial content, texture, and substitutional alloying were evaluated. For unalloyed materials, the tear strength and the fatigue crack propagation rates were generally improved with increasing yield strength, independently of the chemical and structural conditions. Ti-6Al-4V and Ti-5Al-2.5Sn alloys showed reduced tear strengths. Measurement of the unit propagation energy during tear testing was found to be very sensitive to differences in chemistry and structure. (Modified author abstract)

Descriptors :   (*TITANIUM ALLOYS, MECHANICAL PROPERTIES), (*GRAIN STRUCTURES(METALLURGY), TITANIUM ALLOYS), GRAIN SIZE, FATIGUE(MECHANICS), CRACK PROPAGATION, YIELD POINT, TENSILE PROPERTIES, MICROSTRUCTURE, POWDER METALLURGY, NOTCH SENSITIVITY, COLD WORKING

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE