Author: Barbara Kiiskila Lograsso
Publisher:
ISBN:
Category :
Languages : en
Pages : 132
Book Description
The Influences of Hydrogen on the Multiaxial Deformation and Fracture Behavior of Beta Ti-30V and Alpha-Beta Ti-6Al-4V Alloy Sheet
Author: Barbara Kiiskila Lograsso
Publisher:
ISBN:
Category :
Languages : en
Pages : 132
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 132
Book Description
The Influence of Hydrogen on the Multiaxial Fracture Behavior of Titanium Alloy Sheets
Author: B. J. Lograsso
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
The influence of hydrogen on the deformation and fracture of three Ti alloys in the form of sheet has been examined as a function of the state of stress. Unnotched sheet specimens of alpha-phase Ti ( -60, 630, and 980 ppm H), Beta-phase Ti-30V ( -40 and 2000 ppm H), and alpha-Beta Ti-6Al-4V (30, 240, and 500 ppm H) have been investigated over deformation paths ranging from uniaxial to equibiaxial tension. Based on the measurements of the local fracture strains, the alpha-Ti data show a decrease in ductility with increasing hydrogen content as the degree of biaxiality of the tensile strain increases. Thus hydrogen embrittlement of Ti sheet is most severe under equibiaxial straining. In contrast, there is no pronounced effect of stress state on the localized necking and fracture behavior of either the Ti-30V or the Ti-6Al-4V at any of the hydrogen levels/microstructures examined. The results indicate that, even in equibiaxial tension, Ti alloys in the form of sheet are immune to hydrogen embrittlement if hydrides do not form. If hydrides are present, the embrittlement is most pronounced under those state of stress (e.g., plane strain and equibiaxial tension) which are characterized by large normal stresses.
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
The influence of hydrogen on the deformation and fracture of three Ti alloys in the form of sheet has been examined as a function of the state of stress. Unnotched sheet specimens of alpha-phase Ti ( -60, 630, and 980 ppm H), Beta-phase Ti-30V ( -40 and 2000 ppm H), and alpha-Beta Ti-6Al-4V (30, 240, and 500 ppm H) have been investigated over deformation paths ranging from uniaxial to equibiaxial tension. Based on the measurements of the local fracture strains, the alpha-Ti data show a decrease in ductility with increasing hydrogen content as the degree of biaxiality of the tensile strain increases. Thus hydrogen embrittlement of Ti sheet is most severe under equibiaxial straining. In contrast, there is no pronounced effect of stress state on the localized necking and fracture behavior of either the Ti-30V or the Ti-6Al-4V at any of the hydrogen levels/microstructures examined. The results indicate that, even in equibiaxial tension, Ti alloys in the form of sheet are immune to hydrogen embrittlement if hydrides do not form. If hydrides are present, the embrittlement is most pronounced under those state of stress (e.g., plane strain and equibiaxial tension) which are characterized by large normal stresses.
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 756
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 756
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
International Aerospace Abstracts
The Effects of Hydrogen on the Deformation and Fracture Behavior of the Metastable Beta-titanium Alloy, TIMETALĀ® 21S
Government Reports Announcements & Index
Maco/Micro Studies of Hydrogen Embrittlement Mechanisms in Titanium and Aluminum Alloys
Author: W. W. Gerberich
Publisher:
ISBN:
Category : Alloys
Languages : en
Pages : 25
Book Description
Systematic studies of environmental effects on fracture in two alpha/beta titanium alloys, one beta titanium alloy and 7475 aluminum alloys have been accomplished. Ti-6Al-6V-2Sn has been tested for its hydrogen-induced cracking behavior under sustained loads. The influence of frequency and microstructure on fatigue crack growth have also been studied. Fatigue crack growth in Ti-5A1-4Mo, as a function of hydrogen content, temperature and Widmanstatten colony size, was then studied. Mechanical data have been obtained along with TEM and SEM characterizations. Modelling for fatigue thresholds has been attempted to explain dislocation, microstructure and hydrogen effects. Ti-30 Mo has been studied for effects of hydrogen on dislocation dynamics, cleavage fracture stress and fatigue crack propagation. Fractography (SEM) has been used to characterize the fracturing processes and modeling attempted to explain the hydrogen effects. Hydrogen effects in aluminum alloys are not as obvious as those in titanium alloys. Both cathodic and gas-phase charging did not significantly increase the hydrogen content of this material. Mechanical properties did not seem to change decisively after hydrogen charging. But the lack of a macroscopic effect does not preclude a hydrogen mechanism in environmentally assisted events. (Author).
Publisher:
ISBN:
Category : Alloys
Languages : en
Pages : 25
Book Description
Systematic studies of environmental effects on fracture in two alpha/beta titanium alloys, one beta titanium alloy and 7475 aluminum alloys have been accomplished. Ti-6Al-6V-2Sn has been tested for its hydrogen-induced cracking behavior under sustained loads. The influence of frequency and microstructure on fatigue crack growth have also been studied. Fatigue crack growth in Ti-5A1-4Mo, as a function of hydrogen content, temperature and Widmanstatten colony size, was then studied. Mechanical data have been obtained along with TEM and SEM characterizations. Modelling for fatigue thresholds has been attempted to explain dislocation, microstructure and hydrogen effects. Ti-30 Mo has been studied for effects of hydrogen on dislocation dynamics, cleavage fracture stress and fatigue crack propagation. Fractography (SEM) has been used to characterize the fracturing processes and modeling attempted to explain the hydrogen effects. Hydrogen effects in aluminum alloys are not as obvious as those in titanium alloys. Both cathodic and gas-phase charging did not significantly increase the hydrogen content of this material. Mechanical properties did not seem to change decisively after hydrogen charging. But the lack of a macroscopic effect does not preclude a hydrogen mechanism in environmentally assisted events. (Author).
INTERMEDIATE TEMPERATURE CREEP AND RUPTURE BEHAVIOR OF TITANIUM AND TITANIUM BASE ALLOYS PART III; EFFECTS OF HOT ROLLING, EMBRITTLEMENT, AND INTERSTITIAL ELEMENTS
Author: Jeremy V. Gluck, James W. Freeman
Publisher:
ISBN:
Category :
Languages : en
Pages : 115
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 115
Book Description
Report on Hydrogen in Titanium and Titanium Alloys
Author: Dean N. Williams
Publisher:
ISBN:
Category : Titanium
Languages : en
Pages : 116
Book Description
Publisher:
ISBN:
Category : Titanium
Languages : en
Pages : 116
Book Description