...A. Mehmanparast; C. M. Davies; K. M. Nikbin The development of the ASTM E2760-10, “Creep/Fatigue Crack Growth Testing” standard has initiated a phase of testing, analysis, and round robin initiatives associated with high temperature cyclic loading crack growth tests. Creep and fatigue are two...

... propagation is discussed. KEYWORDS: thermomechanical fatigue, crack growth, coatings, microstructure Introduction The continuous increase of operation temperatures of advanced gas turbines during the last decades required application of protective coatings against high temperature oxidation and corrosion...

...Zhigang Wei; Fulun Yang; Henry Cheng; Kamran Nikbin In this paper a deterministic creep/fatigue accumulation model from simple sequential and repetitive creep and fatigue crack growth mechanisms for creep-brittle materials is developed. In the model the maximum stress intensity factor and stress...

...R. A. Ainsworth; D. W. Dean; P. J. Budden Fitness-for-service assessments of components operating at high temperature often require estimates of creep crack growth in service. Although methods for calculating creep crack growth are given in R5 and other codes, these methods are limited in terms...

... to evaluate the J values via standard specimens. The basic method obtains J estimates using the η factor method that was developed for a stationary crack. The resistance curve method obtains crack growth corrected J estimates using an incremental equation that was proposed by Ernst et al. (“Estimation on J...

... make fatigue or crack growth life prediction more difficult. Under low stress level/high cycle fatigue testing, residual compressive stresses have been shown to increase the fatigue strength of the material leading to an “infinite life” and consequent “run-out” of test coupons at the test hole...

... front was nearly half-elliptical shape. The model based on the critical distance concept is presented for expressing crack growth rate in terms of creep damage accumulation in a process zone ahead of the crack tip. An engineering approach to the prediction of residual lifetime of a turbine rotor which...

... plasticity and the redistribution of residual stresses due to the contact loading. The use of superposition of the residual stresses into the contact stress analysis results in unconservative crack growth life predictions. Finite element analyses were conducted to predict the redistribution of residual...

...John J. Ruschau; James C. Newman, Jr. The scope of this paper is to determine the fatigue-crack growth rates in the near-threshold regime for both an aluminum and titanium alloy using the compression precracking constant-amplitude (CPCA) test method on compact specimens. Tests were conducted over...

... for simulating crack growth at R =−1 at variable amplitude loading especially when considering mild steels such as A1N. The aim of the present research is to discuss the application of state-of-the-art algorithms to estimate the effect of block loading at R =−1 (derived from real load spectra experienced...

...SC Forth; JC Newman, Jr; RG Forman The ASTM standard for fatigue crack growth, E 647, was co-developed by industry and government in the late 1970s to define a standard procedure for generating material crack growth behavior under a variety of loading conditions. The standard specifies tolerances...

...SC Forth; JC Newman, Jr; RG Forman The accurate representation of fatigue crack threshold, the region defining crack growth as either very slow or nonexistent, is extremely important. If the experimentally measured threshold is unconservatively high, a structural component designed with this data...

... using BE- (Boundary Element-) methods. The results allow an extension of the rules in Eurocode 3. 31 10 2003 25 10 2004 01 06 2005 brittle fracture steel structures toughness requirements boundary element methods crack growth 2003-11-19 - 2003-11-21 Fatigue and Fracture...

...) linear superposition of stress intensity factor, K, solutions of the non-cold worked hole and the residual stresses. Such predictions have shown various levels of agreement with the overall fatigue life and have generally underpredicted the crack growth over the majority of life. An inverse process...

...MA James; JC Newman, Jr This paper compares area-average and unloading compliance crack-growth values with experimental crack-front shapes recorded at various stages of crack growth during fracture tests conducted on 2024-T351 aluminum alloy plate. Crack-front shapes were determined by fracturing...

... with a failure probability of about 0.05 % from the probabilistic calculations. 14 01 2003 13 05 2004 03 01 2005 creep fatigue crack growth crack initiation life prediction 316L(N) probabilistics 2003-11-19 - 2003-11-21 Fatigue and Fracture Mechanics: 34th Volume...

.... This paper explores the familiar Paris equation relating crack growth rate and applied stress intensity to illustrate many statistical realities that are often ignored by otherwise careful engineers. Although the examples are Monte Carlo, the lessons also apply to other methods of probabilistic life...

... with decreasing stress level has been reported in other materials [10,11]. However, there also are studies where the scale of variability did not change significantly with stress level [12 14]. It seems that, whenever total life largely is composed of crack growth, for example, in the case of aluminum alloys...

... assumptions of linear elastic fracture mechanics begin to break down, and local (microscopic) conditions can lead to significant deviation in fatigue crack growth rate from the global (macroscopic) trend. Fatigue crack life prediction for a large population of fielded components requires a probabilistic...