Author: C. E. EllsPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Susceptibility of zirconium alloys to delayed hydrogen embrittlement
Author: C. E. EllsDelayed Failure Hydrogen Embrittlement of Zirconium. Summary Report, September 15, 1961 to September 14, 1962
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The extent to which zirconium and zirconium alloys exhibit delayed failure (static fatigue) as caused by a combination of absorbed hydrogen and applied stress was investigated. Susceptibility to time-dependent fracture was evaluated for unalloyed zirconium and Zircaloy-2 with 200 and 500 ppm hydrogen as well as for an experimental Zr Al-Sn-Mo alloy and the Canadian Zr-2.5Nb cladding material. For unalloyed zirconium and Zircaloy-2 containing up to 500 ppm hydrogen, no room-temperature, timedependent fracture occurred which could be definitely attributed to the delayed failure phenomenon; an increased grain size, 20% cold deformation by rolling, or corrosion in 750 deg F steam did not significantly affect this behavior. The curve of applied stress versus time to failure at room temperature for the high-strength Zr-Al-Sn--Mo alloy containing 500 ppm hydrcgen established a strong susceptibility to delayed failure due to hydrogen absorption; studies on vacuum-annealed material showed no failures. Further, reduced temperature indicated that the occurrence of static fatigue is temperature dependent. Data for heattreated Zr 2.5Nb containing 500 ppm hydrogen indicated that this material is moderately sensitive to delayed failure at room temperature; higher hydrogen contents caused a greatly increased susceptibility to time-dependent fracture. (auth).
Susceptibility of Zirconium Alloys to Delayed Hydrogen Cracking
Author: JFR AmblerPublisher:
ISBN:
Category : Crack initiation
Languages : en
Pages : 19
Book Description
Smooth and notched cantilever beams and round-notched bars were machined from pressure tubes of cold-worked Zr-2.5Nb and Zircaloy-2. They were loaded in the temperature range 290 to 520 K. After two thermal cycles and at high stress, cracks were initiated in smooth beams of cold-worked Zr-2.5Nb. Under the same test conditions, cold-worked Zircaloy-2 plastically deformed with no cracking. When notches were present, cracks propagated at the same rate in both materials by delayed hydrogen cracking. In cold-worked Zr-2.5Nb, the crack velocity followed an Arrhenius plot with an apparent activation energy of 42 kJ/mol. Below 420 K, the threshold stress intensity factor for delayed hydrogen cracking was about 5 MPa m. Therefore, cracking can be prevented by keeping tensile stresses very low.
Susceptibility of zirconium alloys to delayed hydrogen cracking
Author: C. E. ColemanDelayed Failure Hydrogen Embrittlement of Zirconium. Quarterly Report No. 3, March 15, 1962-June 14, 1962
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
An investigation was made to determine the extent to which zirconium and zirconium alloys exhibit delayed failure (static fatigue) as caused by a combination of absorbed hydrogen and applied stress. Evaluation of susceptibility to time-dependent fracture was performed on an experimental Zr-- Al-- Sn-- Mo alloy containing 500 ppm hydrogen and the Canadian Zr-2.5Nb cladding material, as well as unalloyed zirconium and Zircaloy-2. For unalloyed zirconium and Zircaloy-2 containing up to 500 ppm hydrogen, no time-dependent fracture was observed which could be attributed to the delayed failure phenomenon; an increased grain size or 20% prior reduction by cold rolling did not significantly affect this behavior. The curve of applied stress versus time to failure for the high-strength Zr--Al-Sn-- Mo alloy containing 500 ppm hydrogen indicated susceptibility to time-dependent fracture due to hydrogen absorption. Short-time data for Zr-2.5Nb2 in the heat-treated condition and containing 500 ppm hydrogen indicated that this material is insensitive to delayed failure. (auth).
Delayed Failure Hydrogen Embrittlement of Zirconium. Quarterly Report No. 2, December 15, 1961 to March 14, 1962
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The purpose of this investigation is to determine the extent to which Zr and Zr alloys exhibit delayed failure (static fatigune) as caused by a combination of absorbed H and applied stress. Both notched and unnotched specimens of unalloyed Zr and Zircaloy-2 were hydrogenated to 200 ppm and 500 ppm by means of a modified Sieverts apparatus; specimens were evaluated at room temperature. Thus far, no time-dependent fracture was observed which can be attributed to the delayed failure phenomenon; it appears that these materials are relatively insensitive to static fatigune. The effects of grain size, temperature, cold deformation, and superheated water and steam corrosion on susceptibility to delayed failure are being determined. (auth).
Susceptibility of Cold-worked Zirconium-2.5 WT% Niobium Alloy to Delayed Hydrogen Cracking
Author: C. E. ColemanPublisher: Chalk River, Ont. : Metallurgical Engineering Branch, Chalk River Nuclear Laboratories
ISBN:
Category :
Languages : en
Pages : 25
Book Description
Susceptibility of Cold-worked Zirconium-2.5 WT% Nobium Alloy to Delayed Hydrogen Cracking
Author: Atomic Energy of Canada LimitedPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Hydriding of Zircaloy-2
Author: Myra S. FeldmanPublisher:
ISBN:
Category : Zircaloy-2
Languages : en
Pages : 156
Book Description
Zirconium in the Nuclear Industry
Author: George P. SabolPublisher: ASTM International
ISBN: 0803124996
Category : Microstructure
Languages : en
Pages : 953
Book Description