This paper studied the key factors affecting the amplitude of a composite ultrasonic wiredrawing vibration system, for designing a powerful ultrasonic vibration system. The finite element analysis (FEA) was performed. The results showed that the variable cross-section shapes of horns and the angles between the connection of both ends of the cross-section and the center line had great effects on the amplitude of an ultrasonic vibration system. In order to valid the theoretical result, the experiments were carried out on a composite ultrasonic vibration system. The experimental result demonstrated that the conical variable cross-section rods used in an ultrasonic vibration system produced large amplitude.

To solve the technical difficult problem of difficult-to-draw materials, this work presented a composite ultrasonic vibration system with variable cross-section rods. The four-terminal network method and the finite element method were used to design the conical, the exponential and the catenary transducers. The finite element results of show that the oval trajectory can effectively improve the friction effect between the wire and the tool head. The experimental result showed that the maximum amplitude was about 60 μm. It was 3 times of that in our previous work. These results demonstrated the design of the composite ultrasonic vibration system was feasible.

This paper firstly presented a mathematical model of the radial stiffness of a wire race ball bearing in a certain type of three-axis aircraft simulating rotary table. The Stribeck theory was used to determine the radial load distribution of the bearing. By treating the contact between balls and wires as equivalent compression springs, the relationships of these springs in series and parallel can be obtained to solve the total radial stiffness. Experiments verified the theoretical results of the radial stiffness. This work provides an effective support for further studying the complex contact dynamics of the wire race ball bearing in the future.

The stearate surface modified LDHs S-NiMgAl-Y was rapidly synthesized based on the coprecipitation coupled with the microwave hydrothermal treatment. The cone calorimeter data confirmed that composite S-NiMgAl-Y/EVA has the good functions of both the flame retardancy and smoke/toxic gas suppression. The tensile strength of S-NiMgAl-Y/EVA was increased to the maximum value of 25.6 MPa when the addition of 10 wt.% S-NiMgAl-Y to EVA. This value is markedly larger than that of the pristine EVA equaling 20.8 MPa. The composite material developed in the present work greatly contributes to the processing and application of the fire retardant material.