Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721587025
Category :
Languages : en
Pages : 28
Book Description
Constant-Kmax fatigue crack growth tests were performed on two finegrain nickel-base alloys Inconel 718 (DA) and Ren 95 to determine if these alloys exhibit near-threshold time-dependent crack growth behavior observed for fine-grain aluminum alloys in room-temperature laboratory air. Test results showed that increases in K(sub max) values resulted in increased crack growth rates, but no evidence of time-dependent crack growth was observed for either nickel-base alloy at room temperature. Newman, John A. and Piascik, Robert S. Langley Research Center NASA/TM-2003-212443, NAS 1.15:212443, L-18314, ARL-TR-3021
Near-Threshold Fatigue Crack Growth Behavior of Fine-Grain Nickel-Based Alloys
Author: John A. Newman
Publisher:
ISBN:
Category : Fracture mechanics
Languages : en
Pages : 16
Book Description
Publisher:
ISBN:
Category : Fracture mechanics
Languages : en
Pages : 16
Book Description
Near-Threshold Fatigue Crack Growth Behavior of Fine-Grain Nickel-Based Alloys
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721587025
Category :
Languages : en
Pages : 28
Book Description
Constant-Kmax fatigue crack growth tests were performed on two finegrain nickel-base alloys Inconel 718 (DA) and Ren 95 to determine if these alloys exhibit near-threshold time-dependent crack growth behavior observed for fine-grain aluminum alloys in room-temperature laboratory air. Test results showed that increases in K(sub max) values resulted in increased crack growth rates, but no evidence of time-dependent crack growth was observed for either nickel-base alloy at room temperature. Newman, John A. and Piascik, Robert S. Langley Research Center NASA/TM-2003-212443, NAS 1.15:212443, L-18314, ARL-TR-3021
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721587025
Category :
Languages : en
Pages : 28
Book Description
Constant-Kmax fatigue crack growth tests were performed on two finegrain nickel-base alloys Inconel 718 (DA) and Ren 95 to determine if these alloys exhibit near-threshold time-dependent crack growth behavior observed for fine-grain aluminum alloys in room-temperature laboratory air. Test results showed that increases in K(sub max) values resulted in increased crack growth rates, but no evidence of time-dependent crack growth was observed for either nickel-base alloy at room temperature. Newman, John A. and Piascik, Robert S. Langley Research Center NASA/TM-2003-212443, NAS 1.15:212443, L-18314, ARL-TR-3021
The Near Threshold Fatigue Crack Growth Behavior of a Nickel-based Superalloy
Author: George John Gikas
Publisher:
ISBN:
Category : Alloys
Languages : en
Pages : 0
Book Description
Publisher:
ISBN:
Category : Alloys
Languages : en
Pages : 0
Book Description
A Critical Analysis of Grain-Size and Yield-Strength Dependence of Near-Threshold Fatigue-Crack Growth in Steels
Author: G. R. Yoder
Publisher:
ISBN:
Category :
Languages : en
Pages : 27
Book Description
Though a number of investigators have examined the influence of microstructural variables on near-threshold fatigue-crack growth rates in steels, a comprehensive understanding of the dependence of near-threshold growth rates on grain size, yield strength and microstructural morphology in steels has yet to emerge -- as noted in an excellent review by Ritchie. Recently, however, from our own extensive studies with alpha/beta titanium alloys, the basis for microstructural dependence of widely different fatigue crack growth rates was established for titanium alloys. Inasmuch as the micromechanistic model from that work does not depend uniquely on alloy family, it is of great interest to explore its applicability to steels -- especially since it predicts quantitatively the influence of yield strength and grain size in the near-threshold region for steels. Thus, the purpose of this paper is to critically analyze the near-threshold fatigue crack growth behavior, as reported in the literature, for steels of widely different strength level, grain size and microstructural morphology -- in the search for a systematic ordering of near-threshold fatigue crack growth rates that pertains to the whole gamut of steels. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 27
Book Description
Though a number of investigators have examined the influence of microstructural variables on near-threshold fatigue-crack growth rates in steels, a comprehensive understanding of the dependence of near-threshold growth rates on grain size, yield strength and microstructural morphology in steels has yet to emerge -- as noted in an excellent review by Ritchie. Recently, however, from our own extensive studies with alpha/beta titanium alloys, the basis for microstructural dependence of widely different fatigue crack growth rates was established for titanium alloys. Inasmuch as the micromechanistic model from that work does not depend uniquely on alloy family, it is of great interest to explore its applicability to steels -- especially since it predicts quantitatively the influence of yield strength and grain size in the near-threshold region for steels. Thus, the purpose of this paper is to critically analyze the near-threshold fatigue crack growth behavior, as reported in the literature, for steels of widely different strength level, grain size and microstructural morphology -- in the search for a systematic ordering of near-threshold fatigue crack growth rates that pertains to the whole gamut of steels. (Author).
Near-Threshold Crack Growth in Nickel-Base Superalloys
Author: HR. Van Stone
Publisher:
ISBN:
Category : Crack closure
Languages : en
Pages : 24
Book Description
The influence of stress ratio on the elevated-temperature crack growth behavior of the nickel-base superalloys René 95 and Alloy 718 is discussed. The near-threshold and Region II crack growth behavior of a wide variety of microstructures for each alloy are explained using phenomenological descriptions of closure, that is, K-dependent or K-independent closure. K-dependent closure is the type of closure observed for nickel-base superalloys where increasing the R-ratio causes a uniform lateral shift of the entire fatigue crack growth curve. K-independent closure is the type commonly reported for steels and titanium alloys where increasing the R-ratio has a larger influence on near-threshold crack growth than on Region II crack growth. The existence of K-dependent closure in nickel-base superalloys results in microstructurally sensitive crack growth rates, even at high R-ratios. This permits the use of K-based crack growth prediction techniques and simplifies alloy and process development for applications having complex loading spectra.
Publisher:
ISBN:
Category : Crack closure
Languages : en
Pages : 24
Book Description
The influence of stress ratio on the elevated-temperature crack growth behavior of the nickel-base superalloys René 95 and Alloy 718 is discussed. The near-threshold and Region II crack growth behavior of a wide variety of microstructures for each alloy are explained using phenomenological descriptions of closure, that is, K-dependent or K-independent closure. K-dependent closure is the type of closure observed for nickel-base superalloys where increasing the R-ratio causes a uniform lateral shift of the entire fatigue crack growth curve. K-independent closure is the type commonly reported for steels and titanium alloys where increasing the R-ratio has a larger influence on near-threshold crack growth than on Region II crack growth. The existence of K-dependent closure in nickel-base superalloys results in microstructurally sensitive crack growth rates, even at high R-ratios. This permits the use of K-based crack growth prediction techniques and simplifies alloy and process development for applications having complex loading spectra.
Near Threshold Corrosion Fatigue Crack Growth Behavior of a Nickel Base Superalloy in Air and Inert Environments
Author: James Lum Yuen
Publisher:
ISBN:
Category : Iron-nickel alloys
Languages : en
Pages : 412
Book Description
Publisher:
ISBN:
Category : Iron-nickel alloys
Languages : en
Pages : 412
Book Description
Accelerated Near-Threshold Fatigue Crack Growth Behavior of an Aluminum Powder Metallurgy Alloy
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 11
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 11
Book Description
Fatigue Crack Growth Behavior in Alloy C415 in the Near Threshold Region
Author: Ashok Saxena
Publisher:
ISBN:
Category : Aluminum alloys
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category : Aluminum alloys
Languages : en
Pages :
Book Description
Nano and Microstructural Design of Advanced Materials
Author: M. A. Meyers
Publisher: Elsevier
ISBN: 0080537235
Category : Technology & Engineering
Languages : en
Pages : 317
Book Description
The importance of the nanoscale effects has been recognized in materials research for over fifty years, but it is only recently that advanced characterization and fabrication methods are enabling scientists to build structures atom-by-atom or molecule-by molecule. The understanding and control of the nanostructure has been, to a large extent, made possible by new atomistic analysis and characterization methods pioneered by transmission electron microscopy. Nano and Microstructural Design of Advanced Materials focuses on the effective use of such advanced analysis and characterization techniques in the design of materials. - Teaches effective use of advanced analysis and characterization methods at an atomistic level - Contains many supporting examples of materials in which such design concepts have been successfully applied
Publisher: Elsevier
ISBN: 0080537235
Category : Technology & Engineering
Languages : en
Pages : 317
Book Description
The importance of the nanoscale effects has been recognized in materials research for over fifty years, but it is only recently that advanced characterization and fabrication methods are enabling scientists to build structures atom-by-atom or molecule-by molecule. The understanding and control of the nanostructure has been, to a large extent, made possible by new atomistic analysis and characterization methods pioneered by transmission electron microscopy. Nano and Microstructural Design of Advanced Materials focuses on the effective use of such advanced analysis and characterization techniques in the design of materials. - Teaches effective use of advanced analysis and characterization methods at an atomistic level - Contains many supporting examples of materials in which such design concepts have been successfully applied
Near Threshold Fatigue Crack Propagation Behavior in Iron and Al - 3% Mg Alloy
Author: Dong-Hwan Park
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description