Accession Number : AD0877899

Title :   Strain-Transformable Beta Titanium-Base Alloys.

Descriptive Note : Final technical rept. 1 Jul 69-1 Aug 70,

Corporate Author : BATTELLE MEMORIAL INST COLUMBUS OH COLUMBUS LABS

Personal Author(s) : Wood, Richard A. ; Williams, Dean N. ; Boyd, J. Douglas ; Rothman, Robert L. ; Bartlett, Edwin S.

Report Date : DEC 1970

Pagination or Media Count : 155

Abstract : The objective of the program was to develop a beta titanium alloy which has very good room-temperature formability and capability for precipitation hardening to high strength levels subsequent to forming. The approach used was to develop beta-titanium alloys having strain-transformation capability. This type of beta alloy was found to be extremely formable on the basis of tensile- and Olsen-cup-test evaluations. In comparison with unalloyed titanium in tensile testing, some of the more strain-transformable beta alloys were found to have two to three times the uniform elongation, and in cup testing they showed up to 23 percent improvement (cup height). Further, precipitation-hardening treatments (aging) on some of these same strain-transformable compositions resulted in strength levels of up to 190 ksi with a yield strength/density ratio exceeding 1,000,000 inch. The usefulness of such materials in a variety of applications is obvious. Secondary objectives of interest were pursued during the course of alloy development work. The study of compositional effects was of course paramount. In addition, the effects of beta grain size, cooling rate, and deformation rate and the microstructural characteristics of the strain-transformation product were studied. About 20 of the more than 70 alloys studied look promising. (Author)

Descriptors :   *AGE HARDENING), (*TITANIUM ALLOYS, X RAY DIFFRACTION, ELECTRON MICROSCOPY, TENSILE PROPERTIES, STRAIN HARDENING, COLD WORKING, HEAT TREATMENT.

Subject Categories : Metallurgy and Metallography
      Fabrication Metallurgy

Distribution Statement : APPROVED FOR PUBLIC RELEASE