This purpose of this paper is to examine the relationship between crack growth equations based on Elber’s original plastic wake induced crack closure concept and the fatigue threshold as defined by the American Society for Testing and Materials...
Underload cycles with small load amplitudes below the fatigue crack growth threshold are dominantly considered as insignificant cycles without any influence on fatigue lifespan of engineering structural components. However, this paper shows that in s...
The effects of influential fatigue testing factors, including loading schemes (e.g., traditional load shedding and staircase load increasing), morphology of crack starters, and precracking approaches on the near-threshold fatigue crack growth behavio...
The behavior and the mechanism of fatigue crack propagation in CrCoNi medium-entropy alloys (MEAs) with heterogeneous microstructures were investigated in this paper. After cold-rolling and recrystallization annealing at different temperatures and ti...
Under cyclic loading, fatigue limits ΔσFL and fatigue crack growth (FCG) thresholds ΔΚth are usually examined using the S-N (or ε-N) and FCG da/dN-ΔK approaches, respectively. Historically, these two approaches a...
This study investigates the fatigue damage evolution mechanisms of D2 wheel steel under high-cycle uniaxial and multiaxial loading conditions, with a focus on determining the fatigue crack growth threshold (FCGT). Uniaxial and multiaxial FCGT tests w...
In this article, we discuss an unusual pattern in long-crack behavior at low stress intensity factor ranges ΔK (below ΔKth), characterized by an initial dip, followed by a plateau, and then an acceleration in fatigue crack growth (FCG) ra...
Despite being designed considering infinite fatigue-life, failures of motor crankshafts forged from DIN 34CrNiMo6 steels have been reported in Brazilian power plants. As such, the present work aims to discuss the failure of a crankshaft within this c...
In the field of long-life fatigue, predicting fatigue lives and limits for mechanical components is crucial for ensuring reliability and safety. Fracture mechanics tools have enabled the estimation of fatigue lives for components with small cracks or...
Understanding short fatigue-crack propagation behavior is inevitable in the defect-tolerant design of structures. Short cracks propagate differently from long cracks, and the amount of crack closure plays a key role in the propagation behavior of sho...
The robust determination of the threshold against fatigue crack propagation
This article presents the results of deformation characteristics and crack stress thresholds of cement stone under different acid treatment times. A series of true triaxial tests were conducted on cement stones under four sulfuric acid treatment time...
The resistance to near-threshold fatigue crack growth and its correlation with the microstructure of the Ti-5Al-3Mo-3V-2Zr-2Cr-1Nb-1Fe alloy were investigated. K-decreasing fatigue crack propagation rate tests were conducted on compact tension sample...
Fatigue of materials, like alloys, is basically fatigue-crack growth in small cracks nucleating and growing from micro-structural features, such as inclusions and voids, or at micro-machining marks, and large cracks growing to failure. Thus, the trad...
Effects of the stress ratio on the very high cycle fatigue behaviors of 9%Cr turbine steel have been investigated at 630 °C. The experimental results show that the S–N curve has a continuous downward trend and has no fatigue limit with the...
The fatigue crack growth behavior of unreinforced and particulate reinforced Al 2017 alloy, manufactured by powder metallurgy and additional equal-channel angular pressing (ECAP), is investigated. The reinforcement was done with 5 vol % Al2O3 particl...
The focus of this investigation was to examine the influence of dissolved hydrogen on the fatigue crack growth behavior of an austempered low-alloy AISI 4140 steel. The investigation also examined the influence of dissolved hydrogen on the fatigue th...
A new temperature stress test machine (TSTM) was developed to improve temperature control accuracy and efficiency. As there is no uniform standard for the threshold value of TSTM, quite different threshold values are used in the test, which results i...
The present study analyzes the cyclic crack propagation behavior in an austenitic steel processed by electron beam powder bed fusion (PBF-EB). The threshold value of crack growth as well as the crack growth behavior in the Paris regime were studied....
TiB-reinforced Ti-3Al-2.5V matrix composites, in which TiB whiskers are oriented parallel to the direction of heat extrusion, were fabricated via mechanical alloying and hot isostatic pressing (HIP). To investigate the near-threshold fatigue crack pr...
MIL-STD-1530D and the United States Air Force (USAF) Structures Bulletin EZ-SB-19-01 require an ability to predict the growth of naturally occurring three-dimensional cracks with crack depths equal to what they term an equivalent initial damage size...
In the field of construction engineering, the cracking of concrete structures is a common engineering problem, which has a great impact on the overall stability and service life of the engineered structure. During structural repair, crack detection i...
Crack-growth behavior in yttria-stabilized zirconia-based thermal barrier coatings (TBCs) is investigated through a cyclic thermal fatigue (CTF) test to understand TBCs’ failure mechanisms. Initial cracks were introduced on the coatings’...
Fatigue crack propagation in near-threshold regime was studied in the 304L austenitic stainless steel in two microstructural states: as-received (AR) with finer microstructure and low susceptibility to the transformation-induced plasticity (TRIP) eff...
This work systematically investigates the high-cycle fatigue (HCF) properties and fatigue crack growth (FCG) behavior of hot-rolled dual-phase (DP) steels with comparable tensile strength but distinctly different yield strength (458 MPa for the FG sa...
The corrosion and stress corrosion cracking (SCC) behaviors of 20#, X60, and X80 pipeline steels in a near-neutral pH environment were investigated by means of electrochemical measurement, immersion test, and interrupted slow strain rate tensile (SSR...
The United States Air Force (USAF) Guidelines for the Durability and Damage Tolerance (DADT) certification of Additive Manufactured (AM) parts states that the most difficult challenge for the certification of an AM part is to establish an accurate pr...
Implants are widely used in the human body for the replacement of affected bones. Fatigue failure is one of the serious concerns for implants. Therefore, understanding of the underlying mechanism leading to fatigue failure is important for the longev...
The relationship between tearing energy and crack growth rates in elastomers is typically divided into three regions—slow crack growth, fast crack growth, and a transitional region—each described by separate power law relationships, requi...
Cracks in a building can potentially result in financial and life losses. Thus, it is essential to predict when the crack growth is reaching a certain threshold, to prevent possible disaster. However, long-term prediction of the crack growth in newly...
Shot peening is an attractive technique for fatigue enhanced performance of metallic components, because it increases fatigue crack initiation life prevention and retards early crack growth. Engineering design based on fatigue crack propagation predi...
A fitting method capable of describing the fatigue crack growth rate (FCGR) data in all stages of crack propagation by a simple Forman-style analytical formula was developed. To demonstrate its robustness, this method was used to quantify the fractur...
(1) Modeling and characterization of ductile fracture in metals is still a challenging task in the field of computational mechanics. Experimental testing offers specific responses in the form of crack-mouth (CMOD) and crack-tip (CTOD) opening displac...
Cracks in concrete structures, caused by aging, adjacent construction, and seismic activity, pose critical risks to structural integrity, durability, and serviceability. Traditional monitoring methods based solely on absolute thresholds are inadequat...
The fracture evolution and the strength characteristics of a jointed rock mass under hydro-mechanical coupling are key issues that affect the safety and stability of underground engineering. In this study, a kind of transparent rock-like resin was ad...
Leaf springs are critical components for the railway vehicle safety in which they are installed. Although these components are produced in high-strength alloyed steel and designed to operate under cyclic loading conditions in the high-cyclic fatigue...
The infrared radiation response characteristics and mechanisms of sandstone samples under uniaxial compression were investigated using infrared thermal imaging and strain measurement techniques. The stress–strain curves were divided into differ...
This paper first examines crack growth in a range of tests on additively manufactured (AM) and conventionally manufactured Inconel 718. It is shown that whereas when the crack growth rate (da/dN) is plotted as a function of the range of the stress in...
Short fatigue cracks in polycrystalline materials are very important from both practical and basic aspects, yet they are very difficult to observe. Therefore, it is suggested to emulate some properties of short cracks with long fatigue cracks in mono...
This paper firstly reveals that when assessing if a bonded joint meets the certification requirements inherent in MIL-STD-1530D and the US Joint Services Standard JSSG2006 it is necessary to ensure that: (a) There is no yielding at all in the adhesiv...
In this paper, the low cycle fatigue resistance of a 304L austenitic stainless steel in a simulated pressurized water reactor (PWR) primary water environment has been investigated by paying a special attention to the interplay between environmentally...
Failure analysis and fatigue life prediction are necessary and critical for engineering structural materials. In this paper, a general methodology is proposed to predict fatigue life of smooth and circular-hole specimens, in which the crack closure m...
The different creep-aging forming processes of 2524 aluminum alloy were taken as the research object, and the effects of creep-aging temperature and creep stress on the fatigue-crack propagation properties of the alloy were studied. The research resu...
The growth of cracks between plies, i.e., delamination, in continuous fibre polymer matrix composites under cyclic-fatigue loading in operational aircraft structures has always been a very important factor, which has the potential to significantly de...
The effects of temperature on bulk hydrogen concentration and diffusion have been tested with the Devanathan–-Stachurski method. Thus, a model based on hydrogen potential, diffusivity, loading frequency, and hydrostatic stress distribution arou...
In this article, we characterize and review the unusual lack of threshold in fatigue crack growth (FCG) behavior for some alloys at low values of stress intensity factor ranges ΔK and its implications to damage-tolerant design approaches. This...
This study investigates the fracture behavior of recycled aggregate concrete by integrating fractal theory and empirical modeling to quantify how recycled coarse aggregates (RCAs) and recycled fine aggregates (RFAs) influence crack complexity and max...
This study investigated the effect of pre-deformation on the corrosion fatigue crack propagation (CFCG) of Al-Mg-Zn alloy in a corrosive environment. Tensile tests at different pre-deformation levels and molecular dynamics simulations analyzed change...
This article describes research that investigated the ability of a carbon nanotube (CNT) sensor to detect and monitor fatigue crack initiation and propagation in metal structures. The sensor consists of a nonwoven carrier fabric with a thin film of C...
Double cantilever beam (DCB) tests were conducted by immersing the specimens in temperature-controlled water while applying a creep load using a spring. By introducing a data reduction scheme to the spring-loaded DCB test method, it was confirmed tha...
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