A novel ultrafast-convert high-frequency variable polarity welding for aluminum alloy is developed. With X-ray inspection, tensile tests, metallographic analysis and SEM, the ultrafast-convert frequency VPTIG welding process for 5A06 Al alloy is researched. The results show that the welding quality of 5A06 Al alloy is improved obviously by the ultrafast-convert frequency VPTIG welding technology.
According to the problem of mode selection for detecting disbonding in adhesive bonding structure by using Lamb waves, the relationship between vibration displacement of points in plate and sensitivity of disbonding testing is studied. The experiments are carried out on the steel/rubber adhesive bonding structure by using Lamb waves of different modes. The results show that testing sensitivity of different Lamb waves are different, and a high sensitivity of disbonding testing can be reached by selecting the Lamb modes of which the vibration displacement is larger on plate surfaces than that inside the plate.
A simple but powerful FLC （Fuzzy Logic Controller） design method in put forward by using sliding mode switching surface as a sole fuzzy input variable. It achieves good performance for liquid level control. The total number of rules of the single input fuzzy controller is greatly reduced compared to conventional FLC. The design and tuning of controllr are more simple and easy. At the same time this kind of fuzzy controller is equivalent to the quasi-sliding mode controller, so the robust property and stability is guaranteed well. Experiment result of a tank control shows that it is conscientiously feasible and deserves to be widely applied in the process of controlling industry.
Based on the thermal elastic-plastic FEM （Finite Element Method）, the thermody-namics model of laser welding has been set up, by three dimensional ANSYS finite software element, with APDL language Supported by ANSYS, FES （Finite Element Simulation） of temperature field, stress field in laser welding of BT20 Titanium Alloy Mouthpiece is studied. Combined with numerical calculation results, after in-stantaneous air-cooled handing during laser welding, the stress distributed situation of specimen has been analyzed.
In the aviation enterprises, tool management involves so many departments and different tools that they’re hard to manage. To solve these problems, the management flow of tool lifecycle which includes tool design, tool manufacture, tool daily use and tool reject is summarized and analyzed. Meanwhile, another key technology of statistic of tool consumed ration is studied. These key technologies are used to develop the tool management system and get good effect in aviation enterprises.
