Effect of Microstructures on Low Cycle Fatigue Behavior in a TC6 (Ti-6AI-2.5Mo-2Cr-0.5Fe-0.3Si) Titanium Alloy PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Effect of Microstructures on Low Cycle Fatigue Behavior in a TC6 (Ti-6AI-2.5Mo-2Cr-0.5Fe-0.3Si) Titanium Alloy PDF full book. Access full book title Effect of Microstructures on Low Cycle Fatigue Behavior in a TC6 (Ti-6AI-2.5Mo-2Cr-0.5Fe-0.3Si) Titanium Alloy by Zhang SQ. Download full books in PDF and EPUB format.
Author: Zhang SQ
Publisher:
ISBN:
Category : Crack initiation
Languages : en
Pages : 15
Get Book Here
Book Description
The results of an investigation on the low cycle fatigue (LCF) behavior, at room temperature and 400°C for four conventional microstructures (Widmannstatten, basket-weave, equiaxed, and duplex) in a TC6 titanium alloy are presented. The fatigue crack nucleation and propagation in fatigue-tested specimens have been observed by scanning electron microscopy (SEM). The duplex microstructure is associated with the longest LCF life at room temperature and 400°C, while the Widmannstatten microstructure has the shortest. The crack initiation sites and propagation paths were examined and discussed. The cracks primarily initiated along slip bands on the specimen surface for all four microstructures. In addition, many voids appeared along slip bands for the equiaxed microstructure. By linking-up these voids, the formation of microcracks is realized. The propagation of interior cracks in specimens with Widmannstatten structure proceeded by cross-cutting W? platelets by way of a plastic blunting mechanism, whereas for the equiaxed microstructure interior cracks grew by the linking-up of voids by way of a renucleation mechanism.
Author: Zhang SQ
Publisher:
ISBN:
Category : Crack initiation
Languages : en
Pages : 15
Get Book Here
Book Description
The results of an investigation on the low cycle fatigue (LCF) behavior, at room temperature and 400°C for four conventional microstructures (Widmannstatten, basket-weave, equiaxed, and duplex) in a TC6 titanium alloy are presented. The fatigue crack nucleation and propagation in fatigue-tested specimens have been observed by scanning electron microscopy (SEM). The duplex microstructure is associated with the longest LCF life at room temperature and 400°C, while the Widmannstatten microstructure has the shortest. The crack initiation sites and propagation paths were examined and discussed. The cracks primarily initiated along slip bands on the specimen surface for all four microstructures. In addition, many voids appeared along slip bands for the equiaxed microstructure. By linking-up these voids, the formation of microcracks is realized. The propagation of interior cracks in specimens with Widmannstatten structure proceeded by cross-cutting W? platelets by way of a plastic blunting mechanism, whereas for the equiaxed microstructure interior cracks grew by the linking-up of voids by way of a renucleation mechanism.
Author: C. Hoffmann
Publisher:
ISBN:
Category : Aluminum alloys
Languages : en
Pages : 18
Get Book Here
Book Description
The strain-controlled, elevated-temperature, low-cycle fatigue behavior of a near ? titanium alloy, Ti-6Al-2Sn-4Zr-2Mo-0.1Si (Ti-6242S), has been studied in both air and vacuum (10-5 torr) at 525°C over a range of frequency and strain. Of particular interest in this investigation were the influence of microstructure and environment on fatigue behavior. Two different microstructures were obtained by combinations of mechanical processing and heat treatment above and below the ?-transus temperature. Particular attention was given to these microstructural variations and to the effect of environment on the high-temperature low-cycle fatigue behavior of this alloy. The nature of fatigue crack initiation sites was examined by a precision sectioning method. The microstructure was found to have a pronounced effect on fatigue life as well as on the fatigue crack initiation process. Tests performed in vacuum revealed no influence of frequency on fatigue life, which indicated that environmental factors were responsible for the observed frequency effect on tests performed in air. It was also observed that testing in vacuum led to the formation of a number of subsurface crack nucleation sites and to a longer fatigue life. Crack origins in specimens tested in air were located at the surface, and the initiation sites were larger than those observed in vacuum. The features of a fatigue resistant microstructure in addition to environmental effects at elevated temperature are identified and discussed.
Author: Brian Alfred Wilson
Publisher:
ISBN:
Category :
Languages : en
Pages : 308
Get Book Here
Book Description
Author: R. K. Steel
Publisher:
ISBN:
Category :
Languages : en
Pages : 27
Get Book Here
Book Description
The cyclic stress-strain behavior and the S/N behavior of a 'pseudo-elastic' alloy, Ti-6Al-4V of coarsened microstructure, and of a 'plastic' material, copper, are compared. In accord with views recently put forth by Freudenthal, important differences are noted between these two types of materials. These differences include the mode of crack initiation, the intensity of the Bauschinger effect, and the level below macroscopic yeild at which long-life fatigue data lie. (Author).
Author: J. M. Krafft
Publisher:
ISBN:
Category :
Languages : en
Pages : 30
Get Book Here
Book Description
In earlier NRL work, Ti-6Al-4V in four levels of interstitial oxygen content and a single Ti-8Al-1Mo-1V alloy plate were heat treated to alter grain size and/or microstructural character; the effect on fatigue crack propagation rate was measured. In this work, small tensile specimens of these materials are subjected to slow strain-controlled cyclic deformation leading to rupture in the 5-500 cycle range. Indication of crack initiation as well as rupture life are compared relative to the plastic excursion strain. On this basis, effects of grain size and oxygen content are not clearly discriminated. Yet, some of the materials exhibit markedly performance. This improvement seems to be related to a characteristic evolution in the shape of the cyclic stress-strain curve. Here, relative to a full convex hysteresis loop of early cycles, the later cycles exhibit a reduced stress level, or cyclic softening, in the first half of the excursion, followed by a resurgence of strength to initial stress levels in the latter portion. The enhanced strain hardening rate enabling this terminal strength restoration is thought to stabilize the deformation, reducing the amount of stress-relaxation-induced tensile strain. Taking such strain as an increment of damage in a cumulative cyclic creep strain criterion provides a correlation between the evolving shape of the cyclic stress-strain curve and the low cycle fatigue endurance. Results indicate the absolute increase in the terminal plastic strain hardening rate to be a constant of a material, independent of the cyclic strain excursion. (Author).
Author: Hak-Min Kim
Publisher:
ISBN:
Category : Titanium alloys
Languages : en
Pages : 221
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Get Book Here
Book Description
Author: Paul John Bania
Publisher:
ISBN:
Category :
Languages : en
Pages : 362
Get Book Here
Book Description
Author: Vikas Sinha
Publisher:
ISBN:
Category :
Languages : en
Pages : 284
Get Book Here
Book Description
Author: James B. Radziminski
Publisher:
ISBN:
Category : Plasticity
Languages : en
Pages : 236
Get Book Here
Book Description
