In order to develop high quality and efficient welding technology which is suitable for layered bimetallic sheets, based on the Marangoni convection behavior of molten pool in full penetration welding processes, the dissimilar metals co-pool single pass laser butt welding of bimetallic sheets was presented, and the welding of X65/DSS2205 bimetallic sheet was implemented. Metallographic observations indicated that upper and lower welding seam has obvious characteristics of independent metallographic formation, and there are no indecisive boundaries between the two metallographic formations. The EDS results show that under the optimum process conditions (by orthogonal test), the retention rate of alloying elements such as Cr, Ni and Mo were near 97%.

      The ionic liquid beam additive manufacturing technique combines the characteristics of electrochemical deposition and additive manufacturing. It has received extensive attention due to its characteristics of metal manufacturing at normal temperature and liquid beam processing. The evolution history of ionic liquid beam additive manufacturing technique is reviewed briefly. In view of its poor localization and low manufacturing efficiency, the ionic liquid beam additive manufacturing technique based on jet electrodeposition is proposed. Finally, some research focuses and development prospects which are the ionic liquid beam additive manufacturing for special-shaped parts, large structural parts, micro components and multi-functional composite parts are also pointed out.

      Inclined holes processing at 45° on thermal barrier coatings (TBCs) which were deposited on superalloy samples by electron beam physical vapor deposition (EB–PVD) using the ultrafast laser were processed. Then the thermal cycling test was performed on samples with inclined hole at 45°, the changes of the holes in the thermal cycling test and the effect of the holes on thermal barrier coatings spallation failure were studied. The results show that, there is no cracking and re-casting layer in both thermal barrier coating and superalloy on the edge of the hole which processed by ultrafast laser. Ultrafast laser processing does not result in changes in the tissues of the hole edge at the location of the superalloy, which is still typical γ and γ´ tissues. The hole diameter is no obvious change before and after the thermal cycling. But the inner wall of the inclined hole is changed from a clean surface to a surface with obvious oxide. With the increase of the thermal cycling times, the oxide on the surface of the inner wall of the superalloy is exfoliated. The spallation occurs on the thermal barrier coatings surface after 500 times of thermal cycling. Inclined holes at 45° processed by the ultrafast laser does not affect the thermal cycling spallation failure of thermal barrier coatings.

      According to the principle of electromagnetic lens, the size of the beam spot on the workpiece is related to the position and size of the electron beam waist. The change of the diameter of the grid hole and the position of the anode will cause the change of the electric field distribution, which will change the position and size of the electron beam waist, and eventually influence the size of the working beam spot. The electric field distribution and beam trajectory of the electron gun electrostatic lens are obtained by using the EMF simulation software CST. A single variable method was used to simulate the influence of the diameter of the grid hole and the position of anode on the position and size of the electron beam waist, while the intensity of beam was set to 100mA. The simulation results show that when the diameter of the grid hole is 2mm and the distance between the upper surface of anode and the lower end face is 15mm, the position of electron beam waist is highest and the radius is the smallest in the situation of that other parameters are the same. The welding test was carried out by the optimization parameter D=2mm and H=15mm. The welding seam with greater depth to width ratio was obtained. It is proved that the purpose of reducing the size of the working beam spot and optimizing the beam quality is reached.

      Laser melting deposition (LMD) is a typical additive manufacturing technology. Compared to the traditional forming processes, it has a series of features, such as shorter processing cycle, flexible design, higher dimensional accuracy, and environmental protection. Gradient functional material (FGM) is an advanced functional material without obvious interface inside, and the composition and performance graded distribution along thickness. Among the manufacturing method of FGM, LMD not only relieves the stress between different materials, but also ensures the excellent formability of the material, and controls the change and distribution of the microstructure and properties of the formed parts through flexible design. This paper introduces the technical characteristics of LMD, the characteristic and application of FGM, the research progress in manufacturing FGM by LMD at home and abroad, the current research status of team in this field, and the development prospects of the LMD technology for the manufacture of FGM.

      In this paper, the development status of on-line monitoring for the electron beam freeform fabrication are introduced, mainly focusing on the monitoring of the molten pool morphology, the temperature field of forming process and the flow field, with emphasis on the monitoring of the molten pool morphology during the manufacture. At the same time, the prospects of on-line monitoring for the electron beam freeform fabrication are presented, (1) online monitoring the signals of electronic and ion; (2) introduce new signals for online monitoring; (3) real-time tracking each layer’s the quality and height of deposit body; (4) multi-signal collaborative online monitoring.

      As an environmentally friendly and efficient new paint removal technology, laser paint removal is an important branch of laser cleaning technology. The aircraft needs to remove the original paint layer regularly. This paper reviews the industrial application progress of laser paint removal on the surface of aircraft metal skin and composite material components, and the mechanism of laser paint removal on the surface of aircraft metal skin and the surface of composite materials is analyzed in detail. Finally, the development direction of laser paint removal technology in domestic aviation industry is also prospected.

      To solve the problems of reconfigurable flexible tooling in the complexity of the assembly process and the volatility in the using process, a smart assembly and monitoring system which services in the phase of installation and using was developed. In aspect of assembly, building the assembly process based on smart glasses combined with multi-operator cooperation mode achieved the mobile controlling of the laser tracker. In aspect of tooling monitoring, retaining the traditional
monitoring method combined with smart glasses, in addition installing laser displacement sensors on the critical location guaranteed the stability of the tooling. Besides that, the system has been conducted in the assembly plant, which demonstrates that this system can improve reconfigurable flexible tooling assembly efficiency and reduce the difficulty, and can guarantee the stability of the tooling in the using stage.

      To decrease or eliminate milled blades’ profile errors and to solve the problem in leading/trail edge polishing under presetting pressure control, a new polishing technology available to correct machining errors through presetting contact deformation for wheels was proposed in this paper. Firstly, to obtain the real distribution of machining margin on the surface of blades. Secondly, to determine the different material depth of each local position on the blade surface to be removed with polishing and to adjust the polishing paths and presetting the wheel deformation contacting with workpiece according the obtained depths distribution. Finally, to polish the engine blades with a conventional threeaxis machine tool to verify the capability of the proposed method. The polishing results show that the blades profile error distribution was changed from 0.02–0.12mm to –0.04– –0.005mm after polishing, which was successfully controlled within the designed tolerance. Comparing with the conventional polishing technology, the proposed method is of the ability to remove different quantity of material in depth with flexible diamond polishing wheel and to increase blade profile accuracy, which can be widely used to realize the low cost and high precision polishing of small and medium size aero-engine blades.

      Carbon fiber reinforced plastic (CFRP) is widely used in the fields of aerospace, national defense and medical treatment. In the traditional process of drilling CFRP, there exist the problems of delamination at the entrance and exit, tearing and burrs. In the paper, the vibration assisted drilling process is used to improve the traditional process of drilling CFRP. In order to predict the effect of vibration assisted drilling of CFRP effectively, the modeling of finite element simulation of vibration assisted drilling is carried out by combining the constitutive model of CFRP. Firstly, the mechanical model of CFRP is established by considering the existing constitutive model while the cohesive element is used to simulate the interlayer damage. Then the influence of vibration is realized by applying the vibration movement to the boundary condition of cutting tool in the established model of finite element simulation. The finite element model is verified by comparing the simulation results with the experimental results. Finally, the simulation results of traditional drilling and vibrationassisted drilling are analyzed, which demonstrates that the latter one can effectively reduce the thrust force and suppress the burrs and delamination.

      Based on the birefringence of the LiNbO3 (LN) crystal, it firstly designed a electro-optic Q-switching technique with a pre-deflection of LN crystal. This technique can optimize the structure of Q-switched laser oscillators. Then it analyzed the angle of the pre-deflection the LiNbO3 (LN) in theoretical and simulated the relationship between the angle and the length of the crystal. Finally, an experiment was done to confirm the design, and it successfully obtained the pulsed laser, whose pulse width was 15.76ns with a 108mJ energy.

      In order to meet the demand of aeronautical component remanufacturing design, it is proposed to use the high precision laser tracker to control the wing trailing edge structural components and obtain the point cloud data by means of industrial photographic scanning measurements. Finally, by using the obtained point cloud data to make the reverse modeling task, the results of surveying and modeling ar e evaluated by Geomagic and Control. The experimental results show that the method has high accuracy, fast efficiency and satisfies the remanufacturing design requirements, which provides a new measurement idea and method for reverse modeling technology.