Author: Linda Priscilla Beckerman
Publisher:
ISBN:
Category : Tantalum
Languages : en
Pages : 394
Book Description
A Study of the Effects of Stress on Strain Aging in Vanadium and Tantalum
Author: Linda Priscilla Beckerman
Publisher:
ISBN:
Category : Tantalum
Languages : en
Pages : 394
Book Description
Publisher:
ISBN:
Category : Tantalum
Languages : en
Pages : 394
Book Description
Some Strain-aging Effects in Electrorefined Vanadium
Author: George H. Keith
Publisher:
ISBN:
Category : Vanadium
Languages : en
Pages : 34
Book Description
Publisher:
ISBN:
Category : Vanadium
Languages : en
Pages : 34
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1370
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 : 1370
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.
An Investigation Into the Susceptibility of Tantalum and Vanadium to Slow Strain-Rate Embrittlement Due to Oxygen, Nitrogen and Carbon
Author: R. E. Reed-Hill
Publisher:
ISBN:
Category :
Languages : en
Pages : 35
Book Description
The phenomena of slow strain-rate embrittlement was studied in three metal-interstitial systems, tantalum-oxygen, vanadium-oxygen and tantalum-nitrogen. The embrittlement of tantalum by oxygen was investigated on specimens containing four levels of oxygen -- 0.33, 0.50, 0.85 and1.30 atomic percent. All of the compositions showed embrittlement between 500-1000K in specimens deformed at epsilon = 8.8 x 10 to the 4th power sec to the minus one power. Associated with the embrittling phenomenon, and occurring in the same temperature range where the ductility is dropping, and three dynamic strain-aging effects: (a) a yield stress plateau from 300-600K, (b) serrated yielding from 453-600K and an increasing work hardening rate from 300-600K; Scanning electron microscope studies show that failures were by microvoid coalescence at low temperatures changing to a predominantly intergranular mode in the embrittlement range. Study of the vanadium-oxygen system also showed an embrittlement region between 600-875K. This embrittlement was accompanied by a yield stress plateau between 400-600K, an increasing work hardening rate between 300-650K and serrated yielding from 525K to 650K. A high level of titanium impurity limited testing to low oxygen concentrations. Tests on the tantalum-nitrogen system concluded that nitrogen did not produce slow strain-rate embrittlement in this metal although it served as a potent room temperature strengthener. The interval in which embrittlement is expected in this metal is at a sufficiently high temperature that dynamic recovery and sofening take place. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 35
Book Description
The phenomena of slow strain-rate embrittlement was studied in three metal-interstitial systems, tantalum-oxygen, vanadium-oxygen and tantalum-nitrogen. The embrittlement of tantalum by oxygen was investigated on specimens containing four levels of oxygen -- 0.33, 0.50, 0.85 and1.30 atomic percent. All of the compositions showed embrittlement between 500-1000K in specimens deformed at epsilon = 8.8 x 10 to the 4th power sec to the minus one power. Associated with the embrittling phenomenon, and occurring in the same temperature range where the ductility is dropping, and three dynamic strain-aging effects: (a) a yield stress plateau from 300-600K, (b) serrated yielding from 453-600K and an increasing work hardening rate from 300-600K; Scanning electron microscope studies show that failures were by microvoid coalescence at low temperatures changing to a predominantly intergranular mode in the embrittlement range. Study of the vanadium-oxygen system also showed an embrittlement region between 600-875K. This embrittlement was accompanied by a yield stress plateau between 400-600K, an increasing work hardening rate between 300-650K and serrated yielding from 525K to 650K. A high level of titanium impurity limited testing to low oxygen concentrations. Tests on the tantalum-nitrogen system concluded that nitrogen did not produce slow strain-rate embrittlement in this metal although it served as a potent room temperature strengthener. The interval in which embrittlement is expected in this metal is at a sufficiently high temperature that dynamic recovery and sofening take place. (Author).
The Effect of Nitrogen on the Strain Aging and Brittle-ductile Transition of Vanadium
Author: Robert Wayne Thompson
Publisher:
ISBN:
Category : Nitrogen
Languages : en
Pages : 98
Book Description
Publisher:
ISBN:
Category : Nitrogen
Languages : en
Pages : 98
Book Description
Comprehensive Dissertation Index
Author:
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 1116
Book Description
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 1116
Book Description
Strain Aging During Stress Relaxation in Tantalum-oxygen
Author: Krijn Jacobus Reitsma
Publisher:
ISBN:
Category : Tantalum
Languages : en
Pages : 166
Book Description
Publisher:
ISBN:
Category : Tantalum
Languages : en
Pages : 166
Book Description
An Investigation of the Fatigue Behavior of Tantalum Including the Effect of Strain Aging
Author: D. Y. Wang
Publisher:
ISBN:
Category : Tantalum
Languages : en
Pages : 27
Book Description
A study has been made of the fatigue of commercially pure polycrystalline tantalum under axial loading with zero mean stress. A wrought stress-relieved tantalum material and two recrystallized materials, each having different interstitial impurity element contents, were tested at room temperature; also a recrystallized material was tested at an elevated temperature in an argon gas environment. In addition, surface metallographic observations of the mode of surface crack initiation were made. Tests of specimens representing all three conditions indicated the existence of a definite fatigue limit, similar to that of medium to low strength steel. The variation of the fatigue limit and the knee position is influenced by the test temperature and may be predicted by temperature-dependent mobility of the interstitial atom in diffusion. The experimental results appear to confirm the previously proposed theory that the fatigue limit of a body-centered-cubic metal is attributable to the manifestion of strain aging occurring during alternating stressing. An analysis was made to show the effect of strain aging on ftigue as a function of the test temperature and interstitial content, taking into consideration the experimental observations and the present theories of the mechanism of fatigue.
Publisher:
ISBN:
Category : Tantalum
Languages : en
Pages : 27
Book Description
A study has been made of the fatigue of commercially pure polycrystalline tantalum under axial loading with zero mean stress. A wrought stress-relieved tantalum material and two recrystallized materials, each having different interstitial impurity element contents, were tested at room temperature; also a recrystallized material was tested at an elevated temperature in an argon gas environment. In addition, surface metallographic observations of the mode of surface crack initiation were made. Tests of specimens representing all three conditions indicated the existence of a definite fatigue limit, similar to that of medium to low strength steel. The variation of the fatigue limit and the knee position is influenced by the test temperature and may be predicted by temperature-dependent mobility of the interstitial atom in diffusion. The experimental results appear to confirm the previously proposed theory that the fatigue limit of a body-centered-cubic metal is attributable to the manifestion of strain aging occurring during alternating stressing. An analysis was made to show the effect of strain aging on ftigue as a function of the test temperature and interstitial content, taking into consideration the experimental observations and the present theories of the mechanism of fatigue.
Energy Research Abstracts
Author:
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 1064
Book Description
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 1064
Book Description
American Doctoral Dissertations
Author:
Publisher:
ISBN:
Category : Dissertation abstracts
Languages : en
Pages : 596
Book Description
Publisher:
ISBN:
Category : Dissertation abstracts
Languages : en
Pages : 596
Book Description