Aiming at the problems of large elastic deformation and low machining accuracy in cutting titanium alloy thin-walled parts, this paper establishes the finite element model of milling titanium alloy thin-walled parts, and simulates and analyses the milling process of titanium alloy thin-walled parts by the statics analysis module of ANSYS 15.0 software. The maximum deformation point of the workpiece in the milling process is determined. Then the combination of cutting parameters that can minimize the deformation is determined by the orthogonal experiments of four factors and four levels. This paper designs the single factor experiments, which study the distribution of the milling force and the deformation law of the parts in the milling process. Moreover, this paper carries out the optimal design of the cutting parameters by orthogonal experiments, which provides a reference for the selection of the cutting parameters for the bending thin-walled parts of titanium alloy.

In recent years, bone defect and bone tissue damage have become common clinical diseases. The development of bionic bone has had an important impact on the repair and reconstruction of bone tissue. Porous scaffolds have the advantages of adjustable pore size and controllable shape, which can solve the problem of mismatch in the process of bone repair, but traditional processing methods cannot overcome the challenge of the preparation of complex porous scaffolds. Therefore, 316L porous stainless steel scaffolds with different pore sizes (200 μm, 300 μm, 400 μm and 500 μm, respectively) were prepared by selective laser melting. Stress and strain were simulated and analyzed by using a finite element simulation method. Combined with a heat treatment experiment, a hardness test, a metallographic observation and a compression test, porous scaffolds were studied. The mechanical properties and microstructures of the scaffolds were studied and analyzed, and the optimized porous scaffolds were obtained. With reasonable melting parameters, the porous scaffolds that could meet the mechanical property requirements of load-bearing bone restorations were prepared by SLM.

Lithium-oxygen batteries have attracted considerable attention in the past several years due to their ultra-high theoretical energy density. However, there are still many serious issues that must be addressed before considering practical applications, including the sluggish oxygen redox kinetics, the limited capacity far from the theoretical value, and the poor cycle stability. This study proposes a surface modification strategy that can enhance the catalytic activity by loading Fe₃C particles on carbon fibers, and the microstructure of Fe₃C particle-modified carbon fibers is studied by multiple materials characterization methods. Experiments and density functional theory (DFT) calculations show that the discharge products on the Fe₃C carbon fiber (Fe₃C-CF) cathode are mainly Li_2−xO₂. Fe₃C-CF exhibits high catalytic ability based on its promotion of the formation/decomposition processes of Li_2−xO₂. Consequently, the well-designed electrode catalyst exhibits a large specific capacity of 17,653.1 mAh g⁻¹ and an excellent cyclability of 263 cycles at a current of 200 mA g⁻¹.

Three-dimensional printing technology has a precise manufacturing process that can control tiny pores and can design individualized prostheses based on the patient’s own conditions. Different porous structures were designed by controlling different parameters such as porosity, using UG NX to establish models with different porosities and using ANSYS to simulate stress and strain. Unidirectional compression and stretching simulations were carried out to obtain stress, strain, and deformation. Based on these data, a porosity was found to approximate the elastic modulus of the humeral bone scaffold. As the porosity increased, the equivalent elastic modulus decreased significantly in the lateral direction, and the maximum stress formed by the porous structure and deformation increased significantly. Four different finite element models and geometric models of cubic, face-centered cubic, honeycomb, and body-centered cubic unit structures were selected. Then these porous structures were simulated for tensile and compression experiments, and the simulation results were analyzed. The forming simulation of the finite element model was carried out, and the evolution of mechanical properties of the porous structure during the 3D printing process was analyzed. The results showed that designing the humeral bone scaffold as a porous structure could reduce the stiffness of the prosthesis, alleviate stress shielding around the prosthesis after surgery, enhance its stability, and prolong its service life. The study provides reference values and scientific guidance for the feasibility of porous humeral bone scaffolds and provides a basis for the research and design of clinical humeral bone scaffolds.

With the development of the modern aircraft, the large-scale thin walled parts have been used in aeronautics and astronautics. In NC milling process, the thin walled plates are very easy to deform which will influence the accuracy and quality. From the point of view of theoretically and numerical calculation, the paper proposes a new analytical deformation model suitable for static machining error prediction of low- rigidity components. The part deformation is predicted using a theoretical big deformation equations model, which is established on the basis of the equations of Von Karman when the linear load acts on thin-wall plates. The part big deformation is simulated using FE analysis. The simulating results shown that the diverse cutting forces, milling location and thickness of the plate may lead to various deformation results.