In this paper, we implement the combined method of drilling stop hole and FRP reinforcement to repair cracked steel plates subjected cyclic tension. The crack initiation growth are experimentally investigated. stress distribution at residual fatigue life evaluated by FEM. effects on prolonging analyzed. results show that effectiveness only using is limited, while has dramatically prolonged life...

In situ ultrasonic fatigue with a cyclic frequency of 20 kHz was employed in an environmental scanning electron microscope (ESEM) to characterize fatigue crack formation and growth in the near alpha titanium alloy Ti–6242S. The role of environment on small fatigue crack initiation and growth was investigated in vacuum and in variable pressures of saturated water vapor, as well as in laboratory ...

This paper presents a three-dimensional crack initiation analysis in a sidegrooved CT specimen. This is achieved with an endochronic damage model proposed recently by Chow and Chen [ 1,2] and discretized for finite element analysis. The damage model enables the quantification of the progressive damage evolution which would not be otherwise possible using the conventional fracture mechanics anal...

Fatigue tests have been conducted on an advanced disc Ni-based superalloy (Low Solvus, High Refractory (LSHR) alloy) at 650 C in air under three-point bend loading to investigate the role of orientation-dependent grain boundary oxidation in crack initiation and early propagation. It is found that crack initiation occurs mainly from bulged grain boundary oxides, and cracks then predominantly pro...

in this paper, three-dimensional modeling of the fatigue crack growth profiles was performed in a simple riveted lap joint. simulation results showed that mode i was dominated on the one side of the plates and the crack straightly grew on this side, while the other side of the plates was in a mixed-mode condition and the crack propagation path was not straight on this side. afterward, the fract...

The fatigue crack initiation in a notched single-crystal nickel-base superalloy component at 500°C was investigated and analysed. A critical plane approach in combination with a critical distance method has been adopted, in which the total shear strain ranges on the discrete slip planes are evaluated. Furthermore, a Coffin-Manson type of expression is used to predict the number of cycles to fat...

Through investigating and comparing the fatigue behavior of an as-forged Mg-6.7Zn-1.3Y-0.6Zr (wt.%) alloy before and after solid solution treatment (T4) in laboratory air, the effect of T4 treatment on fatigue crack initiation was disclosed. S-N curves illustrated that the fatigue strength of as-forged samples was 110 MPa, whereas the fatigue strength of T4 samples was only 80 MPa. Observations...

Medium-carbon steel is commonly used for the rail, wire ropes, tire cord, cold heading, forging steels, cold finished steel bars, machinable steel and so on. Its fatigue behavior analysis and fatigue life estimation play an important role in the machinery industry. In this paper, the estimation of fatigue life of medium-carbon steel with different surface roughness using established S-N and P-S...