Combined with finite element numerical simulation analysis, the hot-spin forming technology of cylindrical AZ80 magnesium alloy parts was studied in the paper. e multipass hot-spin forming of magnesium alloy shell parts was simulated by the ABAQUS software to analyze the stress and strain distribution and change during spinning for the preliminary test process parameters in the magnesium alloy spinning test. en, the process parameters were optimized during the hot spinning test, especially the matching relationship between temperature parameter and thinning rate parameter, and the hot spinning magnesium alloy shell parts with the expected technical specifications were finished. Simulation Analysis of Hot-Spin Forming ofCylindrical Magnesium Alloy Parts e strong spinning of the cylindrical part (generally called flow spinning) is a typical partial loading, point-by-point deformation forming process, which has the advantages of labor saving, material saving, and flexibility. It is a metal near

Because of the limited space and high cost of offshore platforms, the dispersion and dissolution of the polymer are required to be of high efficiency, which is essential for polymer injection to enhance hydrocarbon recovery. The numerical simulation models of the water–powder mixing process by Venturi jetting and air-mixing were established. The multiphase flow fields in the water jet ejector, water–powder mixing head, and stirring tank were numerically simulated by FLUENT. Then, the distributions of velocity, volume fraction, pressure, and turbulent kinetic energy of each phase were obtained to evaluate the effects of polymer dispersion and the dissolution of the two mixing methods. According to the maximum velocity of the mixture at the Venturi jet, the optimized length of the throat is 25 mm in our models. The results of the air-mixing process show that a 120° angle of support rods has the best effect of water–powder mixing. The results of the present study show that compared with air-mixing, the combination of Venturi jet and the stirring tank can obtain a broader agitation range and more extensive effect on the flow field, which could uniformly disperse the polymer powder into water. This study has a guiding significance for the design of the onsite polymer injection process.

The press hardening steel with thick specification has been used as automobile chassis parts. With the increase of the thickness, the cooling rate of the inner core is lower in the conventional process, resulting in a poor harden ability, and the fatigue test is not qualified. In this study, the microstructure of hot forming parts with thick specifications was studied by means of metallographic and micro-hardness testing. The results show that there is a microstructure gradient in the thick hot forming parts, which leads to the uneven strength in the cross section and finally affects the fatigue test results.The finite element analysis method is used to study the cooling rate of the inner core of the hot forming parts. The high hardenability press hardening steel products has been prepared by adjusting the components.

As a basic component, electrical connectors play a major role in the transmission and control of electric signals. In this paper, SubMiniature version A (SMA) coaxial connectors, which are widely used in the microwave equipment and radio frequency circuits, were taken as the research objects to investigate the degradation of electrical connectors in salt spray environment. The simulation model was built to analyze the failure mechanism. An accelerated test was conducted to study its electrical contact properties and obtain the degradation data. The experimental and simulation results showed consistent trends. Accordingly, the degradation of the high-frequency performance for the electrical connector in the salt spray environment is mainly due to the formation of corrosion film on the contact surface.

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