The magnetorheological elastomer has a broader potential application due to overcoming the settlement, poor stability, sealing problems and other shortcomings of magnetorheological fluid easily. Firstly the magnetorheological elastomer is prepared, and then it is experimentally proved that the magnetic effect of magneto-rheological elastomers is occurred under magnet field and the stiffness can be also adjusted by controlling the density of field through performance experiments. In this paper, a squeeze mode magnetorheological elastomer vibration isolator and a test rig are designed, it has been shown that the natural frequency of vibration isolator is changed, and the effect of vibration isolation is preferable from the amplitude-frequency characteristic curves for vibration control experiments.

Polyvinylidene Fluoride (PVDF) is becoming a widely used piezoelectric material because of its flexibility, low cost, light weight, and biocompatibility. Its electronic properties, such as its permittivity, can be affected by material crystal structure variations, which also greatly impact the material’s application. It is known that external stress and electrical fields can alter the crystal structure of piezoelectric material. In this research, we aim to investigate the relationship between the external electrical field and the permittivity property of PVDF material. The basic standard equations, finite element analysis, and experimental measurement are included in this paper. By using sweeping voltages from −25 V to +25 V using an Agilent Technologies B1500A Semiconductor Device Analyzer, an increase in the permittivity of the PVDF material is observed. In this work, the study of the permittivity change under the application of different electrical fields at room temperature is presented, and the application of the electrical field under different temperatures is also studied and presented.

composite insulator has been widely used in highvoltage electric power transmission system owing to its advantages such as light weight, anti-pollution flashover and less routine maintenance. With the increasing number of compositor insulators and their running years, the aging of compositors draws attention to the related industries. Considering the aging problems of composite insulator, the material performance of a silicone rubber composite insulator which has worked for more than 10 years on a 500KV transmission line at Guangzhou in China has been analyzed. Judged from the surface, a non-uniform aging characteristic on the different surfaces of the insulator sheds and sheathes exists. The contact angle measurements made on surfaces from different positions confirm the visual aspect of non-uniform aging. In order to explain the phenomenon, the electric field of different positions is computed through finite elements methods. Then the shed and sheath samples on the insulator's various positions were analyzed with Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). At the same time, Thermally Stimulated Current (TSC) was used to find the inner charge difference of both sides of sheds from differentpositions. It is found that electric field intensities and ultraviolet of sunlight are the main factors influencing the aging of the silicone rubber composite insulators. The results will be helpful to the researches of aging problems from composite insulator and its antiaging optimization design.

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Angle Measure Technique (AMT) algorithm is proposed to analyze the quality of batch drilling process in this paper. The groups spindle power (SP) signals of batch drilling were preprocessed by the normalization method, and then the AMT was used to extract the scale features of monitor signals from local to global. By the method of Principal Component Analysis (PCA), the dimensionality of these scale features was reduced to obtain a distribution of the step quality of batch drilling. The results indicate that this method can be used for observation of high precision cutting step quality.