With the unique and combined mechanical, physical and chemical properties of copper and steel, the copper–steel functional materials are widely used in aerospace, power industries, biomedical and other fields. However, the applications of copper–steel functional materials are restricted due to the limitations in producing parts with complex structural design and easy macro segregation at the copper–steel composite interface via traditional methods such as melting and casting. Different from the traditional methods, metal additive manufacturing technology has more advantages in manufacturing copper–steel functional material parts, including capability of complex structure formation and effective alleviation of segregation and other defects at the copper–steel interface attributed to the relatively rapid cooling and solidification process, resulting in the enhancement of interface bonding strength. Based on the recent research progress in the preparation of copper–steel functional materials by various additive manufacturing technologies, the key problems of defects derivation and forming quality of copper–steel functional materials additive manufacturing are analyzed, the practical application scenarios are summarized, and its development trend is prospected.

For the advanced scientific research in extreme environments such as deep space, deep sea, deep earth and polar, the material-structure-functional integrated additive manufacturing for fabricating intelligent components, that is, 4D printing technology was used. The multilayer grid structure of wood was treated as bionic model. The polylactic acid, polycaprolactone, and graphene oxide were treated as the matrix, adding phase and light conversion agents. The bionic smart material with light-responsive shape memory properties was prepared via 3D printing technology of direct writing. The response mode, deformation process, mechanical strength, and deformation temperature of the smart material were researched. The results show that the bionic smart material can return to its original shape in response to light or temperature. The temperature of deformation is lowered to around 55 ℃. Under the near-infrared light response, shape fixed rate is as high as 96%, shape recovery rate is 93%, and the fastest shape recovery time is 9 s. Finally, the application to the bionic deployable structure and the optical response cladding release device were demonstrated, which can achieve light-driven deployment on demand and controlled sequential release functions. It provided an effective bionic new thought and method for solving the problems of accurate selection, remote control, and rapid response in aerospace deformable structures.

Titanium alloys are favored in the aerospace industry due to their high specific strength, high specific stiffness, and high temperature resistance. Only through alloying method, titanium alloys cannot meet the demand of aerospace equipment with service temperatures higher than 600 ℃, such as ultra-high-speed aircraft and new aero-engines. To achieve better high-temperature performance, one of the effective ways is to tailor in-situ synthesized hybrid reinforcements into hightemperature titanium alloys. The resulting new composites, also known as heat-resistant titanium matrix composites (HRTMCs), have received widespread attention because of their increased service temperatures of 50 – 200 ℃ compared to traditional titanium alloys. Regarding the development of HRTMCs, the corresponding research progress and application status were reviewed in terms of design and preparation of microstructural architectures, near-net-shape processing technology (including additive manufacturing, precision casting, isothermal superplastic forming) and high-temperature mechanical properties. Finally, the remained problems and future research directions of the HRTMCs were also pointed out.

Creep tests at 1150 ℃ , 80 – 150 MPa were carried out in a 3rd generation single crystal superalloy DD33. The fracture morphology and damage characteristics in longitudinal section were studied by SEM, EBSD, EDS and TEM. The effect of stress on the fracture mechanisms was analyzed. The results show that the casting pores near the fracture are almost polyhedral, and cracks initiated at the corner of pores. Compared with the lower stress, more creep pores and cracks were induced at 150 MPa. Besides, at 80 MPa, the γ/γ′ matrix bears an extra 35 MPa effective stress due to the thick oxidation affected zone. The highly-localized topologically close-packed (TCP) phase can be found nearby the fracture, and some pores as well as cracks exist at TCP/γ′ interface. With the further increase of applied stress, more surface cracks penetrate into the matrix and more carbides are cracked. Thus, the final failure of the alloy not only directly relates to the internal pores and the pore-induced cracks, but also the effect of the oxidation affected zone, surface cracks penetrating into the matrix, cracks at TCP/γ′ interface and cracked carbides should be considered.

Ultra-high temperature oxide ceramics have excellent strength and structural stability, as well as outstanding oxidation and corrosion resistance at elevated temperatures, which are expected to become new ultrahigh temperature structural materials for long-term service under extremely high temperature oxidation environments. Laser additive manufacturing (LAM) technology represented by selective laser melting (SLM) and laser engineered net shaping (LENS) has the unique advantages of high efficiency, flexible manufacturing, and engineered net shaping. In recent years, it has been gradually applied to the preparation of ultra-high temperature oxide ceramics and has become a research hotspot in the field. In this paper, the technical principles and characteristics have been overviewed for SLM and LENS. The research progress of solidification defect control during the LAM processes for ultra-high temperature oxide ceramics has been investigated in detail from four aspects: process optimization, high temperature preheating, ultrasonic assistance, and doping. Finally, the development trend and research focus have been prospected for ultra-high temperature oxide ceramics by LAM.

The cutting thickness model and the chip sector angle model for low frequency vibration assisted hole making with two cutting edges are established, the chip separation conditions are established, and the empirical formula between the chip sector angle and the cutting angle displacement is proposed. The chip shape analysis test was carried out, by which the corresponding relationship between the hole making parameters and the chip shape was obtained, and the A– f parameter combination range corresponding to the better chip shape was determined. The sector angle of the chip was measured, which was compared and analyzed with the theoretical calculation value, and the result shows that the established chip sector angle model has high accuracy for characterizing the actual chip shape.

In the net-near forming process of aero-engine compressor blade, the leading and trailing edges which have sharply changing curvature and cannot be directly formed need to be processed using NC machining. However, blade will be deformed in the early stage of the process, and the theoretical digital model can no longer be applied to the secondary processing. Therefore, in order to solve the problem of edges machining caused by blade deformation and realize the smooth transfer between blade edge and body, this manuscript presents an adaptive machining method for blade leading and trailing edges based on tool path adjustment. Firstly, the characteristic measurement points are extracted from the formed area near blade edges. And then, the deformation condition of blade in the early process is analyzed by the measurement data. Moreover, the mapping function between the Z coordinate value of the blade section and the deformation law is established according to deformation condition. Finally, the original nominal tool paths are adjusted according to the deformation mapping function and to realize the adaptive machining of blade edges using adjusted tool path. Taking the precision forging blade of a certain aero-engine as an example, the simulation results show that the optimization effect of proposed method is significant. Compared with the machining error using theoretical tool path, the adjusted tool path greatly reduces the machining error. The proposed method can effectively solve the problem of smooth transfer machining between blade edge and body of precision forging blades.

Turbine blade is the core part of aero-engine. It is necessary to register the measured point cloud with CAD model quickly and accurately for NC machining after precision casting. In view of the problem of the initial posit ion and orientation of the measured point cloud, two kinds of pre-alignment algorithms are introduced and implemented, which are the fast alignment based on principal component analysis and manually associated pre-alignment. As for the low efficiency of searching match point, this paper introduces and implements three searching algorithms, which are grid method, normed space projection method and fast search method based on kd–tree. Through comparative analysis, it is pointed out that the fast search method based on kd–tree has better computational efficiency. On this basis, the registration scheme of manual association pre-alignment, match point search based on kd-tree and ICP method is determined. The difference interval between the measured point cloud and CAD model after registration is [–0.06 mm, +0.1 mm], which is accord with the turbine blade casting accuracy.

Aiming at the path following motion of super redundant robot, the end obstacle avoidance path planning method is studied. In the aspect of obstacle modeling, the joint structure and path following motion state of super redundant robot are analyzed, the path constraints are introduced, and the obstacles are inflated; At the level of path planning, the traditional RRT^* algorithm is optimized, and the improved sampling method, the introduction of corner constraint and post collision adjustment are adopted to improve the traditional RRT^* algorithm’s disadvantages such as large random path and complex path. Experimental verification is carried out in MATLAB, and the results show that compared with the path planned by the traditional RRT* algorithm, this method can effectively shorten the path length, reduce the number of nodes, and improve the quality of path planning.

Although digital manufacturing has become an inevitable trend, the lofting template will still play an important role in aircraft manufacturing. Improving the productivity and quality of traditional mode is a subject that requires careful study. Concerning the problems existing in lofting templates inspection, an automatic inspection algorithm based on three-dimensional laser scanning is proposed. For the scribed line, the point cloud of the template is rasterized, the scribed line is roughly extracted according to the height information, and the extraction result is refined by using normal information according to the characteristics of the scribed line. For the shape contour, the edge is extracted from the binary image converted from the point cloud. The result of extraction is registered with CAD digital model, the noise is removed, and the error distribution is printed out by calculating the error between the digital model and the extraction result. The experimental results demonstrate that the proposed method is superior to the existing algorithm in accuracy and efficiency, which is more reliable and efficient than manual inspection. The proposed method has certain value of application in practical engineering.

The structure of the aero-engine casing product is complex, the manufacturing precision is high, and the product processing is very difficult. In order to improve the process design efficiency and quality of aero-engine casing products, the problems that need to be solved in the 3D process design of the casing parts are analyzed, the method of 3D process design is proposed, and the technical route of the 3D process design of the casing parts is constructed. The box products have verified the feasibility of the 3D process technology and laid a solid foundation for the application and promotion of the 3D process in the aero-engine field.