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Uniformity is an important index of the template electrochemical etching. Due to the uneven current distribution between the two electrodes, the etching depth of the workpiece center and edge are significantly different,and the deviation of which is up to 15% or more. In this study, the causes of edge effect is analyzed. A compensation method is proposed and proved by experiments.The results show that: this method is simple, and the uniformity can be reduced to about 3%. It is suitable for the processing of high uniformity requirements in microstructure machining.

The riveting quality has an important influence on the performance of the aircraft structure. The amount of interference can be an important indicator of the quality of riveted structure. The relationship between the clearance between rivet and hole and uniformity of interference is researched theoretically and experimentally against the aviation panel riveted structure. First, the riveting deformation stages are divided, and the deformation law is theoretically analyzed. The test scheme is designed and carried out based on the actual situation. Then, the experiment result is monitored and compensated. Finally, the relationship between the clearance between rivet and hole and uniformity of interfere is given out with the slope of interference as the uniform evaluation index.

Fatigue damage of airframe often caused by riveting defects, which resulting in failure of aircraft structure in service. Based on the theory of classical fatigue fracture, the effects of Interference-fit gap on capabilities of safe service are examined and a new method of measuring the dimension of Interference-fit gap under the different conditions is introduced by cutting test and fatigue test of typical aluminum alloy 2024-T3 in aero industries. And the admissible value of Interference-fit gap for riveting is given, which offered the technological basis to achieve long fatigue of the aircraft.

Differential scanning calorimetry was used to study melt and solidification and microstructure of austenitic stainless steels containing boron. The liquidus and solidus temperatures decreased because of the boron content, and boron inhibited the formation of δ-Fe. A large content of eutectic boride structure was detected when the boron content was higher. The boride was M2B, and the crystal structure was orthorhombic. The crystal structure and elemental composition of M2B were investigated in detail by SEM-EDS and XRD analysis.

By means of power linkage chart method, the model of closed loop pumping system of concrete pump was set up and simulation was carried out in the Matlab. The results show that the hydraulic shock in the closed loop did not occur at the rapid commutation of piston pump and it actually happened when the concrete was pushed forward after compression. The main piston pump commutation is soft action and this shock can be eliminated effectively by means of “SN” control. Closed loop delivery system is used more widely in high volume concrete pumps and is featured by advantages like energy saving, smooth commutation and low hydraulic shock. In this paper, by means of power linkage chart method, the model of the system was set up and dynamics equations set of the system was obtained. A simulation model was set up by means of simulation toolkit in Matlab language – Simulink, in order to have simulation study of commutation shock of the pumping system and shock due to pushing load and obtain the transient performance of model in time domain.

With the development of science and technology, ordered microstructures with special functions have aroused intense research interest .It has been widely used in many fields. This paper summaries the research status in application of the orderly function structure and looks into its future development.