The laser honing technique is a new surface texturing technique. As the piston ring at the top or lower oil attachment point works under worse lubrication condition, its wear increases severely, laser texturing was used to the piston ring/liner, lineary extending grooves and regular arranged dimples with predetermined parameters was well-matched with the needs of lubrication. The effects of different dimple shapes, such as sphere coronal, combined sphere coronal ,columnar, hexahedral, and trapezoidal dimples was analyzed by the theory of hydrodynamic lubrication. It was deduced that trapezoidal dimples are fit for only single running orientation and sphere coronal and combined sphere coronal dimples are fit for double running orientations. The experimental researches show that laser texturing not only can reduce the oil consumption and the cost of engine but also can prolong its work life.

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The 3-D finite element analysis model of beam-edge structure with spaced multiple layers under bird impact is established. Numerical simulations are implemented by using the non-linear contact-impact code ANSYS/LS-DYNA when the birds collide at three locations of the structure respectively. The failure process of the structure and the equivalent plastic strain at supports are obtained. The residual strength of the structure after impact is predicted. The results show that the front spars are penetrated or cracked after the leading edge is perforated. The equivalent plastic strain at the support is much higher when the bird impacts the structure at the central location. Both the structure deformation and failure mode from the simulation are consistent with the results of full scale test, which proves the validity of the method proposed in this paper.

The laser shocking to the Al2O3 ceramics was proceeded, and the fracture microphology that formed from the strong laser shock processing (LSP) was analyzed by the Scanning electron microscopy (SEM). It was discovered that the feature of ceramics responds differently when the laser energy was changed. The brittle fracture that consists of intergranular fracture and cleavage fracture was the main mode under high energy laser shocking (laser pulse enegry: 42J); the macroscopical fracture characteristic was the radial crack. When the laser energy reduced to a fit level (25J), the brittle fracture of ceramics appears to the characteristic of plastic deformation, its fracture microphology appears lots of slippage lines, and the macroscopical feature of radial crack under 42J become subulate crack. While the energy reduced to 15J, the Al2O3 ceramics did not fracture, its micro-hardness ascended, a feature of micro-plastic deformation was existed under the low energy. The reason of the brittle materials appears to the feature of plastic deformation was analyzed.

Laser shock processing is an important surface treatment that induces compressive residual stress to components, where the coating plays an important role. This paper deduce a general formula of the optimum thickness of coating according to the law of energy conservation and analysis the influence of coating on residual stress of the titanium alloy in laser shock processing. Titanium alloy with black paint, silica acid black paint and without coating were shocked by laser system respectively. It was found that coating could increase shock pressure amplitude and laser density absorption. Compressive residual stresses at the surface of the sample with the black paint and silica acid black paint are about -212.2MPa and -264.2MPa respectively, while the surface stress on the uncoated specimen is very high tensile stress. The bare surface due to melting and vaporization, leads to a very rough surface. The depth of induced compressive stress could reduce stress corrosion cracking in titanium alloy and improve fatigue lifetime.