Effect of Mean Stress on Low-Cycle Fatigue Strength of a Medium Carbon Steel S45C True Stress-Controlled Cyclingby Tatsuo ENDO*, Shoji HARADA*, Yoshihiro FUKUSHIMA* and Haruo SAKAMOTO** Nominal stress-controlled low-cycle fatigue life under imposed mean stress is affected by elongation or contraction due to cyclic stress-induced creep. Therefore, the effect of mean stress was examined by a micr...

Guided wave structural health monitoring (SHM) is being considered to assess the integrity of plate-like structures for many applications. Prior research has investigated how guided wave propagation is affected by applied loads, which induce anisotropic changes in both dimensions and phase velocity. In addition, it is well-known that applied tensile loads open fatigue cracks and thus enhance th...

The main purpose of this paper was to investigate the effect of a surface plastic deformation layer introduced by multi-pass ultrasonic surface rolling (MUSR) on the mechanical and fatigue properties of HIP Ti-6Al-4V alloys. Some microscopic analysis methods (SEM, TEM and XRD) were used to characterize the modified microstructure in the material surface layer. The results indicated that the mat...

A method utilizing expansion of a diaphragm-type film specimen was developed to study in vitro biodegradation of poly(etherurethane urea) (PEUU) under conditions of dynamic loading (fatigue). A finite element model was used to describe the strain state, which ranged from uniaxial at the edges of the film to balanced biaxial tensile strain at the center. During testing, the film was exposed to a...

This paper presents an overview of our recent enhanced 3D extended finite element toolkit for Abaqus (XFA3D) for fatigue damage assessment of welded aluminum structures under block loading. To alleviate the computational burden associated with the insertion and propagation of arbitrary cracks in the presence of a welding induced residual stress field, a nodal enriched displacement field coupled...

This paper proposes a method of evaluating the fatigue life of a refrigeration compressor reed valve, given the applied stresses as might be computed by a valve simulation. Mean and alternating values of equivalent stresses (e.g. Von Mises) are plotted in the Haigh diagram. Various choices of models are considered for the safe area of the diagram. This method takes into account surface finish, ...

a nano/ultra-fine grain al-0.2wt% zr alloy was produced by accumulated roll bonding (arb) processafter 10 cycles. the fraction of high angle grain boundaries increased from 8% to 65.4% during 10passes during arb process. this alloy was subjected to tensile test at different temperatures (523,573and 623 k) and strain rates (0.1 and 0.01 s-1). the optimum condition of temperature and strain rate ...

more recently, titanium and aluminum alloys are gaining more interests to be implemented in hydro-forming applications. it is necessary to predict forming limits for these sheet alloys. forming limits play an important role in metal forming processes. forming limit diagrams, present the limit strains for various linear strain paths. in other hand, forming limit curve (flc), illustrates localize...

The ferritic ductile iron (FCD400) is widely used as industrial material. As regards to its high temperature application, fatigue at elevated temperature, and advanced mechanical properties has been investigated and clarified. In low cycle fatigue (LCF), the S-N curve is presented by the relation of plastic strain to the number of cycles as fatigue life, which can be predicted by the Manson-Cof...