...James C. Newman, Jr.; Balkrishna S. Annigeri Plasticity effects and crack-closure modeling of small fatigue cracks were used on a Ti-6Al-4V alloy to calculate fatigue lives under various constant-amplitude loading conditions (negative to positive stress ratios, R) on notched and un-notched...

...D. Gustafsson; J. J. Moverare; K. Simonsson; S. Sjöström Turbine disks are of large importance to turbine designers as they are exposed to hot environment and subjected to high loads. In order to analyze such components with respect to fatigue crack initiation, the work generally starts...

... fatigue high temperature life prediction blades casting failure (mechanical) fatigue cracks fatigue testing gas turbines nickel alloys polymer blends stress analysis stress-strain relations 26 10 2009 22 11 2009 16 08 2010 16 08 2010 2010 American Society...

..., the fatigue crack growth rate for Alloy 617 in air is time independent. This could explain why Hsu’s data for 1.0 Hz and 5.0 Hz is well below the data reported in this work and why the data for 0.1 Hz is within our data range for similar Δ K values. Figure 11 shows the fatigue data with R...

... geometries. Crack nucleation scatter is estimated based on the variability associated with smooth specimen and fatigue crack growth data, including the influences of correlation among crack nucleation and growth phases. The influences of crack nucleation and growth variability on life and probability...

... by the fatigue crack growth phase and is strongly dependent on the magnitude of the stress values in the contact region. These stress values often have the most influence on small cracks where traditional long-crack fracture mechanics may not apply. A number of random variables can be used to model...

... of the turbine section. 14 12 2007 11 11 2008 09 04 2009 blades discs (structures) failure (mechanical) failure analysis fatigue cracks finite element analysis gas turbine power stations mechanical testing nozzles stress analysis surface cracks turbogenerators vibrations...

...Xijia Wu A nonlinear creep/dwell interaction model is derived based on nucleation and propagation of a surface fatigue crack and its coalescence with creep/dwell damages (cavities or wedge cracks) along its path inside the material, which results in the total damage accumulation rate as given by d...

...Irebert R. Delgado; Bruce M. Steinetz; Clare M. Rimnac; John J. Lewandowski The fatigue crack growth behavior of Grainex Mar-M 247 is evaluated for NASA’s turbine seal test facility. The facility is used to test air-to-air seals primarily for use in advanced jet engine applications. Because...

...Srikant Ranjan; Nagaraj K. Arakere A comprehensive fracture-mechanics-based life prediction methodology is presented for fcc single crystal components based on the computation of stress intensity factors (SIFs), and the modeling of the crystallographic fatigue crack growth (FCG) process under mixed...

... with respect to the loading conditions could be accurately determined. 19 07 2006 16 05 2007 11 01 2008 aluminium cast iron engines fatigue cracks fatigue testing life testing thermal stress cracking thermomechanical treatment Due to today’s demands to reduce cost...

... with stress/strain concentrations and stress/strain gradients appear to be the most important sites for fatigue crack initiation. The paper addresses a nonlocal concept for cyclic life prediction of notched components. Contrary to various local approaches in the field, the proposed method explicitly accounts...

... involves considerable postprocessing work. For these reasons, it is very advantageous to develop analytical solution schemes for subsurface stresses, whenever possible. Study of crack initiation under mixed-mode loading is important for understanding fretting fatigue crack initiation in single...

... that predict fatigue crack initiation life, fatigue crack growth life, fatigue limit, fatigue crack growth threshold, crack size at initiation, and fracture toughness. Using microstructure information as material input, the code is capable of predicting the average behavior and the confidence limits...

.... Strazisar. 13 June 2004 01 October 2003 01 March 2004 24 06 2005 jet engines materials testing aerospace test facilities aerospace safety life testing crack detection aerospace materials fatigue cracks discs (structures) The high-temperature high-speed turbine...

..., 2003, Paper No. 2003-GT-38659. Manuscript received by IGTI, October 2002, final revision, March 2003. Associate Editor: H. R. Simmons. 16 June 2003 01 October 2002 01 March 2003 15 04 2005 rotors condition monitoring fatigue cracks vibration measurement crack...

... results in fatigue crack initiation along the “critical” octahedral planes. A “critical plane” fatigue modeling approach was developed in the present study to analyze high cycle fatigue (HCF) failures in single crystal materials. This approach accounted for the effects of crystal orientation...

...Y. Yamashita; M. Shinozaki; Y. Ueda; K. Sakano Fatigue crack growth prediction methods using three-dimensional finite element analyses were investigated to improve the predictability of part-through surface crack growth life. First, a direct analysis method of cyclic finite element analysis...

... on Low Cycle Fatigue Crack Propagation ,” Int. J. Fatigue 0142-1123 , 4 , pp. 4 – 14 . Makhutov , A. Romanov , and Gadenin , M. , 1979 , “ High-Temperature Low-Cycle Fatigue Resistance under Superimposed Stresses at Two Frequencies ,” Fatigue Fract. Eng. Mater. Struct. 8756-758X...

... is generally accepted. Changes to the closure state caused by environmental damage have been invoked. These changes include increased crack surface roughness and debris deposited on the crack faces. Petit 10 has used closure corrected data obtained in vacuum to define an intrinsic fatigue crack growth...