ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Plain and notch fatigue properties of a β-type titanium alloy, Ti-29Nb-13Ta-4.6Zr (TNTZ),which was subjected to various thermomechanical treatments, were investigated in order to judge itspotential for biomedical applications.Microstructures of TNTZ aged at 723 K for 259.2 ks after cold rolling and those aged at 723 K for259.2 ks after solution treatment are composed of a precipitated α phase in the β phase. However,microstructures of TNTZ aged at 598 and 673 K for 259.2 ks after cold rolling and aged at 598 K and673 K for 259.2 ks after solution treatment are composed of a precipitated ω phase, and precipitated αand ω phases in the β phase, respectively. Futher, plain fatigue strengths of TNTZ aged after solutiontreatment and those of TNTZ aged after cold rolling increase with the aging temperature. In particular,TNTZ aged at 723 K after cold rolling exhibits the highest fatigue strength in both the low- andhigh-cycle fatigue life regions. Futher, the run-out, which is about 770 MPa, is nearly equal to that ofhot-rolled Ti-6Al-4V ELI conducted with aging, which is one of the representative α+β-type titaniumalloys for biomedical applications. The notch fatigue strengths of TNTZ aged at stress concentrationfactors of 2 and 6 decrease by 30% – 40% and 50% – 60%, respectively, as compared with the plainfatigue strengths in the low-cycle fatigue life region. Futher, the notch run-out range from 450 to 490MPa and from 220 to 300 MPa, respecitvely; an exception to this is TNTZ aged at 598 K after coldrolling, which has a high volume fraction of the ω phase. Single- and multi- fatigue cracks initiate atthe bottom of the notch at stress concentration factors of 2 and 6, respectively
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/14/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.539-543.557.pdf
Permalink