[en] The maximum shear strain and the normal strain excursion on the critical plane are regarded as the primary parameters of the crack driving force to establish a new short crack model in this paper. An equivalent strain-based intensity factor is proposed to correlate the short crack growth rate under multiaxial loading. According to the short crack model, a new method is proposed for multiaxial fatigue life prediction based on crack growth analysis. It is demonstrated that the method can be used under proportional and non-proportional loadings. The predicted results showed a good agreement with experimental lives in both high-cycle and low-cycle regions.

[en] Cone seal structure is widely used in metal tube connection of industrial equipment and ground vehicle. In vibration environment, the leakage failure of cone seal occur frequently, which will affect the function and reliability of the product directly. In this paper, the contact stress for typical cone sealing structure in low pressure metal tube under vibration loading is analyzed and the mechanism of liquid leakage failure is discussed using the finite element numerical method. Results show that the circumferential contact stress distribution is uneven on the interface of cone sealing structure under the cyclic load introduced by local vibration. The contact stress is significantly lower than the initial pretension stress in some areas, which will result in the leakage failure of cone sealing structure. (paper)

[en] This paper mainly focuses on the entire solutions of a nonlocal dispersal equation with asymmetric kernel and bistable nonlinearity. Compared with symmetric case, the asymmetry of the dispersal kernel function makes more diverse types of entire solutions since it can affect the sign of the wave speeds and the symmetry of the corresponding nonincreasing and nondecreasing traveling waves. We divide the bistable case into two monostable cases by restricting the range of the variable, and obtain some merging-front entire solutions which behave as the coupling of monostable and bistable waves. Before this, we characterize the classification of the wave speeds so that the entire solutions can be constructed more clearly. Especially, we investigate the influence of the asymmetry of the kernel on the minimal and maximal wave speeds.